Tag Archive for: Dauber

Poster presentation at the Pediatric Endocrine Society annual meeting

Encouraging early results for vosoritide in Turner syndrome

Poster presentation at the Pediatric Endocrine Society annual meeting

Roopa Shankar, MD, an endocrinologist at Children’s National Hospital and principal investigator on the study, presented these findings at the Pediatric Endocrine Society annual meeting.

In the world’s first clinical trial of vosoritide for Turner Syndrome (TS), preliminary results show an increase in annualized growth velocity (AGV) in girls with TS in the first six-months of the trial.

Roopa Shankar, MD, an endocrinologist at Children’s National Hospital and principal investigator on the study, presented these findings at the Pediatric Endocrine Society annual meeting on May 17.

The big picture

TS is a rare genetic disorder that occurs in one to about 2,500 girls and is caused by a partial or complete missing X chromosome. Some of the characteristics of TS are short stature, delayed puberty, kidney, thyroid and heart problems. Although there is no cure for TS, many of the symptoms can be treated.

Previously approved for use in achondroplasia, vosoritide is a C-type natriuretic peptide (CNP) analog that binds its receptor on healthy cartilage cells called chondrocytes, leading to increased chondrocyte proliferation and differentiation via its inhibition of the ERK1/2-MAPK pathway.

To date, four participants are enrolled in the trial, and three have completed six months of treatment. Participants with prior growth hormone (GH) exposure increased AGV by +4.9 and +1.57 cm/year over the baseline AGV on GH treatment. The participant without prior GH exposure had an increased AGV +6.04 cm above the baseline at the six-month visit.

What’s next

“The increase in AGV with vosoritide is comparable to the response expected with GH treatment in the GH naïve patient,” says Dr. Shankar. “What’s particularly encouraging is the higher AGV seen in patients previously treated with GH — compared to their baseline on GH alone—which suggests vosoritide may offer additional growth benefits, even when GH responsiveness has diminished. While these preliminary results are very promising, we need longer-term data to establish the safety and the sustained impact on growth. Recruitment for this study is ongoing.”

Find out more about the trial here.

Additional authors from Children’s National include: Niusha Shafaei, MSc, Anqing Zhang, PhD, Kimberly Pitner, MSHS, BSN, RN, Niti Dham, MD, Andrew Dauber, MD, MMSc.

Podcast: Growing hope: Advancing care for kids with growth disorders

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Andrew Dauber, MD, MMSc, at work

Breaking barriers in growth disorder treatment for families

Andrew Dauber, MD, MMSc, at work

Children with hypochondroplasia were previously left with no options for effective long-term treatment, but Andrew Dauber, MD, MMSc, and his team continue to see promising results for treating children with hypochondroplasia using vosoritide.

Paving new roads for families at dead ends

For many children with short stature and other rare genetic growth disorders, there have been no next steps after usual treatment options prove ineffective. Researchers at Children’s National Hospital are digging deeper to find the root genetic causes of short stature disorders and creating novel, nuanced treatment options that have the opportunity to change how the field approaches these cases. From the creation of the growth specialty clinic to creating a study for one patient, the endocrinology team at Children’s National is focused on treating children with the uniqueness that their growth disorders require.

Hypochondroplasia

Many short stature disorders are caused by genetic variations that slow the growth of cells in the growth plate.

Children with hypochondroplasia were previously left with no options for effective long-term treatment, but Andrew Dauber, MD, MMSc, chief of Endocrinology at Children’s National, and his team continue to see promising results for treating children with hypochondroplasia using vosoritide. This drug had previously been approved for treatment of children with achondroplasia, the most common form of dwarfism. Treatment of hypochondroplasia has shown similar and, often, even better results. Study participants have managed the treatment well and have overall been very satisfied with the results.

Children’s National is the only site in the world offering this treatment to patients. The study includes over 50 children from two distinct subsets of patients — those with hypochondroplasia and those with other genetic short stature disorders such as RASopathy conditions, most common of which is Noonan syndrome, and children with mutations in the aggrecan and NPR2 genes. The study has found a significant increase in growth rates for children with hypochondroplasia who underwent treatment with vosoritide for one year.

“These are the first patients in the world to ever receive this medication for their conditions,” said Dr. Dauber. “The results are very promising and may change the way we practice medicine. Patients have come from all over the world to participate in the study.”

The preliminary data is even more promising for children in the study with other genetic conditions, which include defects that are more directly related to C-natriuretic peptide (CNP), which vosoritide targets directly. This is the first medication that directly targets the pathway in chondrocytes (cells in the growth plate that make the bones grow longer) affected by these specific mutations. Those patients are still undergoing their first full year of treatment and results of that section of the study are expected to be released next fall.

“We’re really starting to see this therapeutic landscape open up and develop for patients with this rare condition, for which right now there is no approved therapy, so really exciting times in this space,” says Dr. Dauber.

ACAN study

Dr. Dauber was a part of a study that was the first-of-its-kind to provide genetic testing for children with short stature and their families, finding ACAN gene mutations in multiple family members, and providing hormone therapy to the children impacted. The ability to diagnose this type of gene mutation allows families to be proactive with treatments — both as their child is growing and how other family members can reduce the risk of further complications down the road.

“We’re at the tip of the iceberg with research that explores this gene mutation,” says Dr. Dauber.

Study of one

This type of unique and cutting-edge research isn’t new to the endocrinology team at Children’s National, who is focused on creating unique interventions to find answers for patients and families. When a patient with short stature was found to have a unique mutation in his growth hormone receptor, Dr. Dauber and his team created a single patient trial with a precision medicine approach to overcome the patient’s growth hormone resistance. This isn’t the first time Dr. Dauber led a single patient study. Even when study populations are small, unlocking genetic answers and treatment options for even one patient is at the core of work being done at Children’s National. Dr. Dauber emphasized the importance of these findings for the medical community, particularly for those dedicated to pediatric endocrinology. He noted that understanding the nuanced responses among different children is crucial for optimizing future treatments.

What’s next

Even with improved height and growth outcomes, there is still more to uncover. In addition to the world’s first clinical trial using vosoritide in children for hypochondroplasia, Children’s National researchers are studying the quality of life for children with the disorder and how it may be affected by treatment, aiming to provide this full scope of care for children with these rare conditions. Dr. Dauber and his team continue to study connections between genetic biomarkers and response rates to clinical therapies, with hopes of discovering how these targeted approaches to treatment can be most effective. The work done by the team at Children’s National has shown results to warrant phase three of the trial.

“This ongoing commitment to innovative research underscores the relentless pursuit of targeted therapies, bridging gaps and bringing hope to families and patients worldwide,” says Dr. Dauber.

Dr. Dauber and patient

Innovative treatment for growth disorders

Dr. Dauber and patient

Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology, with a patient.

Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology, leads a program that brings together comprehensive resources for children with rare genetic growth disorders, including basic science, translational and clinical research.

“Discovery is important, and research gives us many answers,” he says. “But what we do with those answers is what really matters. There’s nothing better than seeing the impact our research is having on an individual patient. It is so gratifying to hear from parents about how their kids are making progress thanks to a protocol we developed.”

Mia thrives with the right approach

Middle schooler Mia loves to dance, practice gymnastics and hang out with friends. She was born in Croatia with hypochondroplasia, a genetic disorder that slows cell growth and causes short stature and limb shortening.

Mia practices her dance moves.

Mia practices her dance moves.

She struggled in kindergarten because she was so small. “Kids can be very mean if you’re different,” says Mia’s dad, Ivan. “For years, we took Mia to different specialists in Europe without getting the help she needed. I researched endocrinologists all over the world. They all pointed us to the United States.” This led Ivan to Children’s National and Dr. Dauber.

Dr. Dauber invited the family to the U.S. to participate in a clinical trial that was to start very soon. “I knew this was our only chance,” said Ivan, who rushed to bring his family to Washington, D.C., for the initial screening appointments. They later returned for more measurements, Mia’s first dose of medicine and a three-month supply to go. The family returns to Children’s National every six months.

In Mia’s first year, she grew more than 3 inches. Her arms also grew longer. “Dr. Dauber is probably the best doctor in the world,” Ivan says. “He is like a friend to Mia and has helped us make sure she has as normal a life as possible. This growth, including in her confidence, has been life-changing for her.” The family relocated to the U.S., and Mia will continue in the trial until she reaches puberty.

“Now, the difference between Mia and other kids is much less,” Ivan says. “She makes new friends more easily and is a happy, happy kid. As for me, I want to cry for how happy I am. Dr. Dauber and Children’s National made it all possible.”

test tubes filled with blood and serum

Pharmacokinetic and pharmacodynamic analysis of vosoritide in Phase 2 trial

test tubes filled with blood and serum

The research, published in Hormone Research in Paediatrics, examined whether pharmacokinetic (PK) factors or other blood biomarkers correlated with the response to treatment of vosoritide in children with hypochondroplasia.

Researchers from Children’s National Hospital presented new data from the world’s first clinical trial of vosoritide use for growth disorders at the European Society for Pediatric Endocrinology annual meeting. The research, published in Hormone Research in Paediatrics, examined whether pharmacokinetic (PK) factors or other blood biomarkers correlated with the response to treatment of vosoritide in children with hypochondroplasia. The study found that drug exposure ­­— as measured by average PK area under the curve (AUC) — did not correlate with any growth outcome.

The big picture

Previously published results of the clinical trial of vosoritide in children with hypochondroplasia showed that vosoritide can help kids with hypochondroplasia grow better. For this study, the researchers analyzed PK parameters by non-compartmental methods. Pharmacodynamic markers were measured at day 1, the 6-month and 12-month visits. The PK analysis indicates that drug exposure was correlated to global C-type natriuretic peptide (CNP) activity as measured by urine cyclic guanosine monophosphate (cGMP) concentrations.

Moving the field forward

There are currently no approved therapies for hypochondroplasia. Children’s National is the first site in the world to conduct a trial of a targeted treatment for hypochondroplasia and this is the first study to report PKs of vosoritide in children with hypochondroplasia.

“The results of our study showed that the drug levels achieved are similar to what was achieved in patients with achondroplasia,” says Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology at Children’s National and one of the study authors. “This suggests that the dose we used is a reasonable one, paving the way for a Phase 3 trial of vosoritide in children with hypochondroplasia.”

What’s next

Dr. Dauber emphasized the importance of these findings for the medical community, particularly for those dedicated to pediatric endocrinology. He noted that understanding the nuanced responses among different children is crucial for optimizing future treatments.

“This ongoing commitment to innovative research underscores the relentless pursuit of targeted therapies, bridging gaps and bringing hope to families and patients worldwide,” says Dr. Dauber.

Read the study in Hormone Research in Paediatrics: Phase 2 Trial of Vosoritide Use in patients with Hypochondroplasia: Pharmacokinetic/ Pharmacodynamic analysis from 12 Month Data

model of human growth hormone

Promising results after precision medicine trial for growth hormone resistance

model of human growth hormone

A patient with short stature and growth hormone (GH) resistance experienced a growth rate increase of 3.4 cm/year after 12 months of high-dose GH therapy.

In a first-of-its-kind single-patient clinical trial, a patient with short stature and growth hormone (GH) resistance experienced a growth rate increase of 3.4 cm/year after 12 months of high-dose GH therapy as part of a precision medicine approach. The study, led by Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology at Children’s National Hospital, was published in The Journal of Clinical Endocrinology & Metabolism.

What this means

“Many patients with short stature do not get a definitive genetic diagnosis, and even if they do, it takes substantial effort to design a targeted therapeutic trial,” says Dr. Dauber.

This is the first trial of extremely high-dose growth hormone in a single patient with a unique form of growth hormone resistance.

Children’s National leads the way

During an endocrine evaluation for short stature, which included GH stimulation testing demonstrating growth hormone resistance, a next-generation sequencing panel revealed that the patient had an inherited heterozygous frameshift variant in the growth hormone receptor gene (GHR).

The researchers found that the patient’s growth hormone binding protein (GHBP) levels were elevated because of this variant, limiting circulating GH’s ability to bind to the GH receptor. The researchers believed that, with extremely high doses of GH, the mechanism of resistance would be overcome and normal GH signaling would be restored.

“We found that we were able to overcome the patient’s growth hormone resistance, which resulted in substantially improved growth,” says Dr. Dauber. “Our understanding of the underlying pathophysiology of his growth disorder led to our ability to design a precision medicine trial just for this single patient.”

Genetic testing and translational biology can provide insights into the specific underlying mechanism of rare growth disorders, allowing for precision medicine approaches.

Dr. Andrew Dauber measures Mia's height

First global clinical trial achieves promising results for hypochondroplasia

Dr. Andrew Dauber measures Mia's height

Trial participant Mia Maric is measured by Dr. Andrew Dauber.

Researchers from Children’s National Hospital presented findings from the first clinical trial of the medication vosoritide for children with hypochondroplasia – a rare genetic growth disorder. The results were presented at the 2024 American College of Medical Genetics and Genomics (ACMG) Annual Clinical Genetics Meeting.

The big picture

Recently approved to increase linear growth and open growth plates in children with achondroplasia, vosoritide is a C-type natriuretic peptide analog that binds its receptor on chondrocytes, leading to increased chondrocyte proliferation and differentiation by inhibiting the ERK1/2-MAPK pathway.

“Vosoritide directly targets the pathway in the growth plate that is affected by the genetic mutation causing hypochondroplasia,” said Andrew Dauber M.D., M.M.Sc., chief of Endocrinology at Children’s National and lead author of the study.

During the phase 2 trial, researchers found vosoritide increased the growth rate in children with hypochondroplasia, allowing them to grow on average an extra 1.8 cm per year.

The patient benefit

Ivan Maric’s 11-year-old daughter, Mia, has been participating in the trial for the last 18 months. In 2022, they moved from Croatia to be part of the study.

“This has been life-changing for Mia,” Maric said. “Soon after receiving the initial doses, we immediately noticed growth. Now, she can independently manage everyday tasks such as washing her hair and reaching the sink to wash her hands.”

What’s next

Vosoritide treatment may work as a precision therapy to improve growth in multiple genetic conditions that interact with the ERK1/2-MAPK pathway.

“This study provides a proof of principle that this medicine will work for these children and supports further research in this area,” said Dr. Dauber. “I was excited to see how well tolerated the medication was and how some patients had excellent responses.”

This clinical trial funded by BioMarin is the first-of-its-kind to treat children with genetic short stature who do not have achondroplasia. Other growth-related conditions included in this phase 2 trial were Noonan syndrome, NPR2 mutations and Aggrecan mutations.

Additional authors from Children’s National: Anqing Zhang, Ph.D., Roopa Kanakatti Shankar, M.D., Kimberly Boucher, R.N., Tara McCarthy, B.A., Niusha Shafaei, B.A., Raheem Seaforth, B.A., Meryll Grace Castro, M.S., and Niti Dham, M.D.

Youn Hee Jee

Shaping the future of pediatric endocrinology

Youn Hee Jee

“Select patients will have the opportunity to participate in research studies focused on cutting-edge genomic investigations into their growth disorders,” says Youn Hee Jee, M.D., M.Med., endocrinologist.

“We’re dedicated to unraveling the mysteries that families have long sought answers to,” says Andrew Dauber, M.M.Sc., M.D., chief of Endocrinology at Children’s National Hospital. “There are numerous endocrine and genetic conditions with the potential to impact a child’s growth. That’s why we’ve assembled a team of leading endocrinologists and geneticists to create a new Growth Specialty Clinic and address these issues with a fresh perspective.”

This team, combined with the expertise of the hospital’s translational scientists, is making significant progress in identifying the causes of a variety of growth disorders and developing innovative treatments. And at the core of this work, Dr. Dauber says, is a recognition of the unique impact endocrine disorders have on each individual child.

What’s unique

Leveraging the expertise of Medical Geneticists Natasha Shur, M.D., and Deepika Burkardt, D.O., from the Children’s National Rare Disease Institute – the largest clinical genetics program in the United States – the growth clinic taps into substantial knowledge in the genetics of growth.

Dr. Shur emphasizes the commitment to providing answers for these families. “This collaborative effort goes beyond diagnosis; it opens doors to potential treatment options.”

The Growth Specialty Clinic is for children with severe undiagnosed growth disorders that are suspected to have a genetic etiology and children with rare genetic diagnoses who would benefit from the expertise of practitioners more familiar with those disorders. It is also closely linked to the Center for Genetic Medicine Research.

“Select patients will have the opportunity to participate in research studies focused on cutting-edge genomic investigations into their growth disorders,” says Youn Hee Jee, M.D., M.Med., endocrinologist.

In one case, Dr. Jee identified a new genetic cause of an overgrowth syndrome. Rare genetic conditions known as generalized overgrowth syndromes manifest as excessive body growth during fetal life and/or childhood, frequently resulting in tall stature. She is investigating the mechanisms that promote healthy bone growth.

Additionally, Dr. Jee identified a new genetic cause of short stature. Her research showed that the identified genetic cause impairs the recycling of essential proteins for growth, expanding our knowledge of human growth.

Moving the field forward

“We’re taking innovative approaches to treatment by leveraging our insights into the genetic origin of each patient’s growth disorder,” says Dr. Dauber.

In the brief time since the clinic’s launch, several new diagnoses and treatment pathways have already been offered. In one single-patient study, researchers were able to successfully overcome the patient’s growth hormone resistance using a targeted approach, and the patient has shown significant catch-up growth after one year of treatment.

Children’s National is also at the forefront of other groundbreaking research, launching novel clinical trials that are advancing the field of endocrinology:

  • Vosoritide clinical trial: Children’s National has the first clinical trial in the world testing Vosoritide in children with certain genetic causes of short stature. Researchers have enrolled approximately 50 subjects with exciting preliminary results for patients with Noonan syndrome, Aggrecan gene mutations and NPR2 gene mutations. All 24 hypochondroplasia patients have completed the 18-month trial. Dr. Dauber intends to present results at the 2024 American College of Medical Genetics meeting in Toronto.
  • Hypochondroplasia study: Children’s National is the first site to launch BioMarin’s new natural history study for children with hypochondroplasia which will also be a lead into their future Phase 3 trial.

Read more about our advances in Diabetes & Endocrinology.

DNA strands

Whole genome sequencing solves precocious puberty case

DNA strands

By conducting whole-genome sequencing, doctors were able to discover the cause of a patient’s severe precocious puberty.

A true medical anomaly — a patient with severe precocious puberty starting in infancy later developed bilateral testicular tumors. Despite extensive testing at multiple other hospitals, no one had been able to understand the underlying cause of his precocious puberty. That is until now, through a study led by Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology at Children’s National Hospital.

The hold-up in the field

Before receiving care at Children’s National, the patient’s diagnostic workup was limited by genetic testing modalities and the ability to enroll him in an innovative research protocol.

Moving the field forward

“We were able to enroll the patient in a research protocol that allowed them to sequence his whole genome,” says Dr. Dauber. “Both in a DNA sample from his blood as well as in a sample from one of his testicular tumors, which was being removed surgically.”

Dr. Dauber then performed an analysis of the genome data and found that the patient had a mutation in the luteinizing hormone receptor (LHR), which was present in the testicle but not in his blood. This is called a somatic mutation. The LHR receives the signal from the pituitary gland, which tells the testicle to make testosterone. In this case, the LHR is always turned on, which makes him develop Leydig cell tumors in his testes, overproducing testosterone, causing him to have very early puberty.

By conducting whole-genome sequencing of the tumor and blood samples, the patient was confirmed to have bilateral, diffuse Leydig cell tumors harboring the somatic gain-of-function p.Asp578His variant in the LHCGR gene.

This mutation had been identified before in patients with isolated tumors but never in someone with diffuse bilateral tumors.

The patient benefit

By using cutting-edge genomic approaches, medical providers can identify unknown causes of endocrine disorders. It also stresses the importance of the clinical team working with translational researchers to determine answers for patients.

“With a more definitive diagnosis and understanding of what these tumors are, researchers can better counsel the family about the treatment options,” says Dr. Dauber. Other members of the Children’s National team that contributed to this work include Seth Berger, M.D., Ph.D.; Daniel Casella, M.D.; and Emmanuèle C Délot, Ph.D.

You can read the full study, Precocious Puberty in a Boy With Bilateral Leydig Cell Tumors due to a Somatic Gain-of-Function LHCGR Variant, in the Journal of the Endocrine Society.

DNA

New research on genetic evaluation of short stature, discussed by Andrew Dauber, M.D., M.M.Sc.

DNA

In this study, the authors at Shanghai Children’s Medical Center utilized next-generation sequencing (NGS) to analyze the data of patients with short stature to better understand the etiologies of short stature.

Andrew Dauber, M.D., M.M.Sc., division chief of Endocrinology at Children’s National Hospital, shared expert commentary on a recent study published in The Journal of Clinical Endocrinology & Metabolism that explores associated risk factors of short stature as identified by exome sequencing in children.

In this study, the authors at Shanghai Children’s Medical Center utilized next-generation sequencing (NGS) to analyze the data of patients with short stature to better understand the etiologies of short stature.

The big picture

“This was a large-scale study looking at 814 children with short stature and at least one more clinical feature suggestive of a genetic condition who underwent comprehensive genetic testing at Shanghai Children’s Medical Center,” explains Dr. Dauber. In this study, the authors identified a potential genetic etiology in 361 of the patients, which is 44% of the cohort.

“It is important to note that the yield of genetic testing was highly variable depending on the clinical presentation of the child,” said Dr. Dauber. “For example, patients with associated congenital anomalies or a suspected skeletal dysplasia had a diagnostic yield of 56% and 65% respectively, while patients with isolated severe short stature (defined as a height below -3 SDS) only had a yield of 11%.”

Dr. Dauber noted that the overall high yield is reflective of the types of patients who are referred to this specialty center, and the expected yield in a more general pediatric setting is likely much lower.

The patient benefit

“This study helps shed light on the prevalence of those patients in a large cohort of children presenting for evaluation of short stature,” shared Dr. Dauber. “I am hopeful that targeted treatments will improve growth in these children.”

While this study provides new insights into the underlying causes behind short stature in patients with differing phenotypes, the authors indicate that additional large-scale studies on short stature exome sequencing are warranted.

Moving the field forward

Dr. Dauber also pointed to the fact that the authors note a large number of the patients in this study had undiagnosed Rasopathies, such as Noonan syndrome. “There were also 31 patients with FGFR3 mutations, 6 patients found with ACAN (Aggrecan) mutations and 2 with NPR2 mutations,” said Dr. Dauber.

“At Children’s National, we are currently conducting a clinical trial of vosoritide, a novel growth promoting agent which targets the growth plate in children with selected genetic conditions including Noonan syndrome and patients with mutations in FGFR3, ACAN, and NPR2,” included Dr. Dauber. Preliminary results from this clinical trial were recently presented by Dr. Dauber at the Pediatric Endocrine Society annual meeting.

You can read the full study Clinical Profiles and Genetic Spectra of 814 Chinese Children With Short Stature in The Journal of Clinical Endocrinology & Metabolism.

doctor measuring girl's height

Vosoritide shows promise for children with certain genetic growth disorders

doctor measuring girl's height

This is the first clinical trial in the world testing vosoritide in children with certain genetic causes of short stature, including hypochondroplasia, Noonan syndrome, NPR2 mutations and Aggrecan mutations.

Andrew Dauber, M.D., M.M.Sc., endocrinologist at Children’s National Hospital, presented preliminary results from a phase II clinical trial of a new drug, vosoritide, used to treat children with certain growth disorders, at the Pediatric Endocrine Society annual meeting held virtually on May 1.

Vosoritide is a C-type natriuretic peptide analog that binds its receptor on chondrocytes, leading to increased chondrocyte proliferation and differentiation via its inhibition of the ERK1/2-MAPK pathway.

This is the first clinical trial in the world testing vosoritide in children with certain genetic causes of short stature, including hypochondroplasia, Noonan syndrome, NPR2 mutations and Aggrecan mutations.

To date, 34 participants have enrolled in the trial with a median baseline height of -3.2 SD (interquartile range (IQR) -3.7, -2.6). 18 subjects have initiated on vosoritide and twelve have completed six months of therapy. The authors note that the mean increase in annualized growth velocity (AGV) was 1.8 cm/yr for subjects with hypochondroplasia and 6.1 cm/yr for subjects with Noonan syndrome or NPR2 mutations. The two subjects with NPR2 mutations had increased AGVs of 4.4 and 9.2 cm/yr, while the two subjects with Noonan syndrome had increased in AGVs of 7.5 and 3.3 cm/yr. One of the Noonan syndrome subjects was previously treated with growth hormone (GH) for 2 years and AGV was 6.7 cm/yr while on GH, 4.1 cm/yr during the trial 6-month observation period and 11.6 cm/year during the first six months of vosoritide treatment.

To the researchers, the safety profile is quite reassuring. So far, the preliminary results showed increased growth in all the genetic subgroups with the patients with hypochondroplasia demonstrating a response similar to that seen previously in patients with achondroplasia. While the results are very promising for patients with Noonan syndrome and NPR2 mutations, the clinical trial must be completed before drawing further conclusions. The experts also plan to submit the study to a peer-reviewed journal in the future to validate the findings.

The big picture

This is the first medication that directly targets the pathway in chondrocytes (cells in the growth plate that make the bones grow longer) affected by these specific mutations. This means that the novel approach may give patients additional therapeutic options outside of growth hormone.

Why we’re excited

“These are the first patients in the world to ever receive this medication for their conditions,” said Dr. Dauber. “The results are very promising and may change the way we practice medicine. Patients have come from all over the world to participate in the study.”

Children’s National leads the way

This clinical trial funded by BioMarin is the first of its kind to treat children with genetic short stature who do not have achondroplasia. Children’s National is the only site in the world offering this therapy for patients with these conditions.

Find out more about the trial here.

aggrecan protein

Two new papers advance aggrecan deficiency research

aggrecan protein

Aggrecan (ACAN) is a large protein found in joint cartilage and growth plates.

Andrew Dauber, M.D., M.M.Sc., division chief of Endocrinology at Children’s National Hospital, and colleagues recently published two papers that describe the phenotypic spectrum of aggrecan deficiency and look at treating the condition with human growth hormone.

Aggrecan (ACAN) is a large protein found in joint cartilage and growth plates. It allows joints to move smoothly and without pain. Aggrecan deficiency — due to heterozygous mutations in the ACAN gene — causes dominantly inherited short stature and, in many patients, early-onset osteoarthritis and degenerative disc disease.

Clinical phenotype of patients with aggrecan deficiency

In 2017, Dr. Dauber led an international consortium of researchers that published a manuscript describing the phenotypic spectrum of 103 individuals – 70 adults and 33 children, including 57 females and 46 males – from 20 families with ACAN mutations. In the study, Dr. Dauber and his colleagues established that short stature and accelerated bone age is common among people with ACAN mutations.

In a new study published in the American Journal of Medical Genetics Part A, Dr. Dauber and colleagues further characterize the phenotypic spectrum of aggrecan deficiency, with an emphasis on musculoskeletal health.

Twenty-two individuals from nine families were enrolled in the study. Recorded histories and examinations focused on joint health, gait analysis, joint specific patient reported outcomes and imaging.

“We performed a detailed analysis of the musculoskeletal manifestations in patients with mutations in the aggrecan gene,” says Dr. Dauber. “We found that patients with mutations in this gene had significant short stature which worsened with age. There was a high prevalence of joint complaints and arthritis in adults, and we were able to detect pre-symptomatic joint damage in children using knee MRIs.”

Treating short stature in aggrecan-deficient patients with human growth hormone

Until now, it was unknown how to treat children with aggrecan deficiency. “Providing growth hormone therapy to children with ACAN gene mutations is relatively new in the field of pediatric endocrinology,” explains Dr. Dauber. “Previously, the assumption was that this was just short stature.”

In a new study, published in The Journal of Clinical Endocrinology and Metabolism, Dr. Dauber and colleagues reported the results of a trial that evaluated the efficacy and safety of recombinant human growth hormone (rhGH) therapy on linear growth in children with ACAN deficiency.

“This is the first prospective trial of growth hormone therapy in patients with mutations in the aggrecan gene,” says Dr. Dauber. “Mutations in the gene are the cause for short stature in approximately 2%  of individuals with idiopathic short stature.”

The open-label, single-arm, prospective study enrolled ten treatment-naïve patients with a confirmed heterozygous mutation in ACAN. Participants were treated with rhGH (50 µg/kg/day) over 1 year. Main outcomes measured were height velocity and change in height standard deviation score.

The authors found that growth hormone led to short term improvements in growth rate over the course of the year. The treated patients had their growth rate increase from 5.2 centimeters per year to 8.3 centimeters per year while on therapy.

In 2019, the researchers received the 2019 Human Growth Award at the Pediatric Endocrine Society’s Annual Meeting for an abstract related to this work, entitled “Clinical Characterization and Trial of Growth Hormone in Patients with Aggrecan Deficiency: 6 Month Data.”

Med Games Logo

Continuing medical education through online games

Med Games LogoAndrew Dauber, M.D., MMSc., chief of Endocrinology at Children’s National Hospital, participated as the faculty chair of a Med Games CME educational online activity, to provide continuing medical education for physicians. This game-based activity is intended to meet the educational needs of endocrinologists, endocrine fellows, primary care physicians, physician assistants, nurse practitioners and health care professionals who diagnose and manage children with growth hormone deficiency (CGHD). This CME educational program is provided by Med Learning Group and supported by an educational grant from Novo Nordisk Inc.

Learn more about the program and test your knowledge: ‘Accurate Diagnosis and Effective Management of Children with Growth Hormone Deficiency: What Can You Do to Improve Patient Outcomes in Your Clinical Practice?’

Blood sample tube for anti-Müllerian hormone

A look at the clinical utility of anti-Mullerian hormone

Blood sample tube for anti-Müllerian hormone

Anti-Mullerian hormone (AMH), also known as Mullerian inhibiting substance (MIS), is a hormone produced exclusively in the gonads. It was originally described in the context of sexual differentiation in the male fetus but has gained prominence now as a marker of ovarian reserve and fertility in females.

In a mini-review published in The Journal of Clinical Endocrinology and Metabolism, Roopa Kanakatti Shankar, M.D., pediatric endocrinologist at Children’s National Hospital and an associate professor of pediatrics at the George Washington University School of Medicine and Health Sciences, and co-authors offer an updated synopsis on AMH and its clinical utility in pediatric patients.

The authors performed a systematic search for studies related to the physiology of AMH, normative data and clinical role in pediatrics. After reviewing 70 clinical studies and systematic reviews, they conclude that, “AMH has widespread clinical diagnostic utility in pediatrics but interpretation is often challenging and should be undertaken in the context of not only age and sex but also developmental and pubertal stage of the child.”

Other authors from Children’s National Hospital include Andrew Dauber, M.D., MMSc, Tazim Dowlut-Mcelroy, M.D., and Veronica Gomez-Lobo, M.D.

Read the full review in The Journal of Clinical Endocrinology and Metabolism.

US News badges

For fifth year in a row, Children’s National Hospital nationally ranked a top 10 children’s hospital

US News badges

Children’s National Hospital in Washington, D.C., was ranked in the top 10 nationally in the U.S. News & World Report 2021-22 Best Children’s Hospitals annual rankings. This marks the fifth straight year Children’s National has made the Honor Roll list, which ranks the top 10 children’s hospitals nationwide. In addition, its neonatology program, which provides newborn intensive care, ranked No.1 among all children’s hospitals for the fifth year in a row.

For the eleventh straight year, Children’s National also ranked in all 10 specialty services, with seven specialties ranked in the top 10.

“It is always spectacular to be named one of the nation’s best children’s hospitals, but this year more than ever,” says Kurt Newman, M.D., president and CEO of Children’s National. “Every member of our organization helped us achieve this level of excellence, and they did it while sacrificing so much in order to help our country respond to and recover from the COVID-19 pandemic.”

“When choosing a hospital for a sick child, many parents want specialized expertise, convenience and caring medical professionals,” said Ben Harder, chief of health analysis and managing editor at U.S. News. “The Best Children’s Hospitals rankings have always highlighted hospitals that excel in specialized care. As the pandemic continues to affect travel, finding high-quality care close to home has never been more important.”

The annual rankings are the most comprehensive source of quality-related information on U.S. pediatric hospitals. The rankings recognize the nation’s top 50 pediatric hospitals based on a scoring system developed by U.S. News. The top 10 scorers are awarded a distinction called the Honor Roll.

The bulk of the score for each specialty service is based on quality and outcomes data. The process includes a survey of relevant specialists across the country, who are asked to list hospitals they believe provide the best care for patients with the most complex conditions.

Below are links to the seven Children’s National specialty services that U.S. News ranked in the top 10 nationally:

The other three specialties ranked among the top 50 were cardiology and heart surgery, gastroenterology and gastro-intestinal surgery, and urology.

Drs. Dewesh Agrawal, Andrew Dauber, Robert Freishtat, Vittorio Gallo

Four Children’s National Hospital leaders named to APS

Drs. Dewesh Agrawal, Andrew Dauber, Robert Freishtat, Vittorio Gallo

Drs. Dewesh Agrawal, Andrew Dauber, Robert Freishtat and Vittorio Gallo were named as 2021 American Pediatric Society members.

The American Pediatric Society (APS) has announced 55 new members, four of which are experts from Children’s National Hospital. Founded in 1888, the APS is the first and most prestigious academic pediatric organization in North America.

APS members are recognized child health leaders of extraordinary achievement who work together to shape the future of academic pediatrics. New members are nominated by current members through a process that recognizes individuals who have distinguished themselves as child health leaders, teachers, scholars, policymakers and/or clinicians.

“Our members represent the most distinguished and accomplished academic leaders in pediatrics whose outstanding work has advanced child health,” said APS President Steven Abman, M.D. “I am honored to welcome this exceptional group of individuals to the APS. The APS is especially looking forward to the active engagement of our membership with many exciting programs within the organization that are directed towards improvements in academic pediatric medicine, including more vigorous approaches to express our values of anti-racism, equity, diversity and inclusion.”

APS 2021 active new members from Children’s National are:

  • Dewesh Agrawal, M.D., vice-chair for Medical Education at Children’s National. Agrawal’s career has been marked by academic honors and teaching awards at every stage of his training and faculty employment. He has relentlessly devoted his energy to improving the educational experience for students, residents and fellows at Children’s National.
  • Andrew Dauber, M.D., M.M.Sc., chief of Endocrinology at Children’s National. Dr. Dauber’s leadership is reflected, nationally and internationally, in his ability to create research consortia, bringing together investigators to tackle complex questions. For example, he leads an NIH-funded consortium on the genetics of short statures, with multiple top children’s hospitals as partners. He also leads a large clinical trial testing a novel therapeutic agent for genetic short stature.
  • Robert Freishtat, M.D., M.P.H., senior investigator in the Center for Genetic Medicine of the Children’s National Research Institute (CNRI). Dr. Freishtat has authored or co-authored more than 100 articles and book chapters in the fields of pediatric lung injury, asthma, obesity, exosomes and emergency medicine. His research has been continuously funded by the NIH since 2003.
  • Vittorio Gallo, Ph.D., chief research officer at Children’s National and scientific director of CNRI. Dr. Gallo’s scientific success is attested to by over 130 peer-reviewed publications, many in very high-profile journals, as well as over 30 review articles and book chapters. He has received many national and international awards, including the NINDS Javits award in Neuroscience in 2018. Dr. Gallo has served on the editorial boards of many neuroscience journals, including Glia and the Annual Review in Neuroscience, and has been reviewing editor for the Journal of Neuroscience, all of which is a testament to the tremendous impact that his studies have had on the advancement of neurosciences.

“These new members represent multiple areas of Children’s National and have all leveraged the intersection of science, medicine and clinical education to make advances in their field of study,” said Stephen J. Teach, M.D., M.P.H., chair of the Department of Pediatrics at Children’s National. “Their work has, and will continue to, advance pediatric health care, and I congratulate them on their APS membership.”

little girl measuring her height

Study may change treatment of childhood growth disorders

little girl measuring her height

A new Phase 2 study at Children’s National will look at using the drug vosoritide to promote growth in children with growth disorders.

A child’s growth is often measured by pediatricians during routine physicals to identify abnormalities of growth and stature. An abnormality in these measurements could mean a child has a growth disorder. There are many different causes of growth disorders. Some can be the result of defects in genes related to the growth plate, which is the tissue near the end of long bones that grows as the child grows. Children with a growth disorder can present many different symptoms including short stature, joint pain, heart problems, bone problems and developmental delays. Scientists still have a lot to learn about what exactly causes these genetic growth disorders and treatments are limited, especially in the pediatric population. Growth hormone is not uniformly helpful and has only been approved for a small number of conditions.

Vosoritide is an investigational drug that directly targets the growth plate to promote growth. It is an analog of the amino acid C-type natriuretic peptide (CNP). It binds its receptor on healthy cartilage cells called chondrocytes and is currently under investigation in clinical trials as a treatment for the bone growth disorder achondroplasia.

“Vosoritide for Selected Genetic Causes of Short Stature” is a Phase 2 study currently open at Children’s National Hospital. This study will target five types of genetic short stature including SHOX deficiency, hypochondroplasia, Rasopathies (which includes Noonan syndrome), heterozygous NPR2 defects and CNP deficiency.

Thirty-five children with short stature will be enrolled and followed for a six-month observation period to obtain baseline growth velocity, safety profile and quality of life assessment. Study participants will then be treated with vosoritide for 12 months and will be assessed for safety and improvement in growth outcomes.

“Many patients who present with short stature likely have genetic defects in genes involved in growth plate physiology. Those patients with selected causes of short stature that interact with the CNP pathway may benefit from treatment with vosoritide, which directly targets the growth plate,” said Andrew Dauber, M.D., MMSc., lead investigator of this clinical study and chief of Endocrinology at Children’s National Hospital, a program ranked in the top 10 by U.S. News & World Report. “In this study, our goal is to understand if vosoritide may be a safe and effective treatment option for certain genetically defined short stature syndromes.”

This clinical trial has been approved by the FDA and funded by BioMarin. Children’s National is the only site in the world offering this therapy for patients with these conditions. The study is currently underway and subject recruitment is ongoing. There are 9 participants enrolled to date.

“This study could fundamentally change the way we treat certain growth disorders”, says Dr. Dauber.

For more information on the clinical trial, click here.

DNA moleucle

Genetics can’t explain mixed impact of growth hormone therapy

DNA moleucle

Growth hormone therapy is one of the most common treatments for short stature in children. However, endocrinologists report mixed outcomes, even when children have the same underlying condition as the cause of their short stature. Despite research into a variety of potential causes for this unpredictable response, there is still very little scientific evidence to help physicians predict whether children with short stature who are treated with growth hormone will respond to the treatment or not.

A study published in the Journal of Clinical Endocrinology and Metabolism took up this question with an eye to the genetic factors that might predict response by conducting the first ever genome-wide association study of response to growth hormone.

“Previous disease-specific models have been developed using multiple clinical variables such as parental height, age at treatment start, peak hormone levels and doses, and birth parameters, however, these clinical parameters only partially predict variation in response,” wrote the study authors, including Andrew Dauber, M.D., first author and chief of the division of Endocrinology at Children’s National Hospital. “Our goal was to perform a large-scale genome-wide study to provide a comprehensive assessment of how common genetic variation may play a role in growth hormone response.”

To accomplish this, the study combined five cohorts from across the world to identify 614 individuals for further review. All patients had short stature caused by conditions including growth hormone deficiency, small for gestational age, or idiopathic short stature (no previously identified cause), who received growth hormone as treatment.

Interestingly, the researchers found no overwhelming genetic predictors of response to growth hormone. They did identify a few signals that may potentially play a role in the body’s response to growth hormone but noted those signals will need further exploration. The study also ruled out the idea that genetic predictors of height in the general population might predict response to growth hormone.

“Identifying genetic predictors of how a child with short stature will respond to growth hormone would be an important step forward for clinicians and parents to make informed decisions about the right treatment approach,” says Dr. Dauber. “Though we didn’t find any specific indicators, this large-scale study has allowed us to rule out some previously held assumptions and offers several new avenues to explore.”

The study was conducted in collaboration with Pfizer and Boston Children’s Hospital.

Andrew Dauber

Andrew Dauber, M.D., MMSc, caps off research success with award and reception

Andrew Dauber

Unfortunately, we’ve been notified that the ENDO2020 conference has been canceled due to concerns of COVID-19. Because of this, we will not be hosting our reception in honor of Andrew Dauber, M.D., on Sunday, March 29.

We hope to see you at a future Endocrinology or Pediatric Endocrinology event.

Children’s National Hospital is incredibly proud of the work Dr. Dauber has done in the endocrinology community.

Andrew Dauber, M.D., MMSc, division chief of Endocrinology at Children’s National Hospital, will be awarded the 2020 Richard E. Weitzman Outstanding Early Career Investigator Award at ENDO 2020. The prestigious award will be presented at the annual meeting of the Endocrine Society in recognition of Dauber’s work in understanding the regulation of growth and puberty, and applying innovative genetic technologies to studying pediatric endocrinology. Dauber credits many collaborators throughout the world, as well as the team at Children’s National for the award.

With a five-year grant from the National Institutes of Health (NIH), Dauber and colleagues from the Cincinnati Children’s Hospital Medical Center, Boston Children’s Hospital and the Children’s Hospital of Philadelphia are using electronic health records to identify children who likely have rare genetic growth disorders. Using cutting-edge DNA sequencing technologies, including whole exome sequencing, the researchers are aiming to identify novel genetic causes of severe growth disorders. The first paper describing genetic findings in patients with high IGF-1 levels was published in Hormone Research in Paediatrics in December 2019.

Dauber and researchers at Cincinnati Children’s Hospital Medical Center are exploring how to treat patients with mutations in the PAPPA2 gene. In 2016, the group described the first patients with mutations in this gene who had decreased the bioavailability of IGF-1, stunting their growth and development. In their current phase of research, findings are emphasizing the importance of this gene in regulating IGF-1 bioavailability throughout childhood. The ultimate aim is to create therapies to increase IGF-1 bioavailability, thereby supporting healthy growth and development in children. Their first study to track PAPPA2 and intact IBGBP-3 concentrations throughout childhood was published in the European Journal of Endocrinology in January 2020.

Dauber is particularly interested in studying children with dominantly inherited forms of short stature. Along with collaborators in Cincinnati, he currently has an ongoing treatment trial using growth hormone in patients with Aggrecan gene mutations.  Dauber hopes to announce soon a new clinical trial for children with all forms of dominantly inherited short stature.

Study upon study has shown us that there are many factors that affect an individual’s height and growth. As these studies and the conversation around how to identify and address genomic anomalies become more prevalent, the team at Children’s National is increasingly interested in engaging with other centers around the country. In the coming months, the Children’s National Research & Innovation Campus will open on the grounds of the former Walter Reed Army Medical Center, which will serve as a one-of-a-kind pediatric research and innovation hub. A critical component to this campus is the co-location of Children’s National research with key partners and incubator space.

regional pediatric endocrinology meeting

Regional pediatric endocrinologists gather at Children’s National

regional pediatric endocrinology meeting

On Nov. 10, 2019, more than 30 pediatric endocrine physicians and nurse practitioners from Washington, D.C., Maryland and Northern Virginia gathered at Children’s National Hospital to discuss the latest in pediatric endocrinology research.

Organized by Paul Kaplowitz, M.D., Professor Emeritus of Pediatrics, this was the third regional pediatric endocrinology meeting since 2012 and the second held at the hospital. “The meetings are a great opportunity for providers to meet regional colleagues who they may communicate with about patients but rarely see face to face,” explains Dr. Kaplowitz.

The providers spent half a day at Children’s National viewing presentations and connecting with their colleagues. Among the presentations was a talk by new Children’s National faculty member Brynn Marks, M.D., MSHPEd, titled, “Medical Education in Diabetes Technologies.”

The presentation highlighted Dr. Marks’ research on how to best teach providers to make optimal use of the information provided by continuous blood glucose monitoring, as well as how to adjust insulin pump settings based on frequent blood glucose testing.

Another notable presentation was by Richard Kahn, Ph.D., recently retired former chief scientific and medical officer at the American Diabetes Association. Dr. Kahn’s talk was titled “Prediabetes: Is it a meaningful diagnosis?”

“This was an excellent talk whose message was that making a diagnosis of ‘prediabetes’ may not be nearly as helpful as we thought, since most patients tests either revert to normal or remain borderline, and there is no treatment or lifestyle change which greatly reduces progression to type 2 diabetes,” says Dr. Kaplowitz.

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Children’s National regional pediatric endocrinology meeting presentations

Welcome from Paul Kaplowitz, M.D., and Children’s National Endocrinology Division Chief Andrew Dauber, M.D.

“Prediabetes: Is it a meaningful diagnosis?”
Richard Kahn, Ph.D., University of North Carolina at Chapel Hill

“Overlapping genetic architecture of Type 2 diabetes and Cystic fibrosis-related diabetes”
Scott Blackman, M.D., Ph.D., Johns Hopkins Medicine

“Pediatric Pituitary Tumors: What we have learned from the NIH cohort”
Christina Tatsi, M.D., Ph.D., National Institutes of Health

“Medical Education in Diabetes Technologies”
Brynn Marks, M.D., MSHPEd, Children’s National Hospital

“A phenotypic female infant with bilateral palpable gonads”
Cortney Bleach, M.D., Walter Reed National Military Medical Center

“Estimating plasma glucose with the FreeStyle Libre Pro CGM in youth: An accuracy analysis”
Miranda Broadney, M.D., MPH, University of Maryland School of Medicine

“Recruiting for research project on “Arginine-Stimulated Copeptin in the diagnosis of central diabetes insipidus”
Chelsi Flippo, M.D., Fellow, National Institutes of Health