Pediatric and Adolescent Endocrinology

SUN-211 - Heterogeneity of Growth Response to Vosoritide in Children with Achondroplasia: Impact of Endocrine Comorbidities and Pubertal Status

Sunday, June 14, 2026

9:00 AM - 4:00 PM CT

Location: ENDOExpo; Poster Floor

Abstract Poster Presenter(s)

AB

Amrit Bhangoo, MD (he/him/his)

Pediatric Endocrinologist
Children Hospital of Orange County
Orange, California, United States

Co-Author(s)

AK

Ahmed Khattab, MD

Pediatric Endocrinologist
Rutgers-Robert Wood Johnson Medical School
New Brunswick, New Jersey, United States
EL

Erica Lupiano, BS

Short Hills, NJ, United States
JM

Joshua Matthew, Medical student MS3

Medical student MS3
Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, US
New Brunswick, New Jersey, United States
DH

Deboragh Horlacher, APN

APN
Cooperman Barnabas and Newark Beth Israel Medical Center, RWJBarnabas Health, NJ, US
Livingston, New Jersey, United States
MJ

Marianne Jacob, DO

Pediatric Endocrinologist
Cooperman Barnabas and Newark Beth Israel Medical Center, RWJBarnabas Health
Livingston, New Jersey, United States
AO

Arystan Olzhabek, MD

Pediatric Endocrinologist
Kazakh National Medical University, Almaty, Kazakhstan
Almaty, Kazakhstan
AD

Ayazhan Demeuova, MD

Pediatric Endocrinologist
Kazakh National Medical University, Almaty, Kazakhstan
Almaty, Kazakhstan
NZ

Nazgul Zhunusbekova, MD

Pediatric Endocrinologist
Aksay Children’s Hospital, Almaty, Kazakhstan.
Almaty, Kazakhstan
AK

Amangul Kudaikulova, MD

Pediatric Endocrinologist
Kazakh National Medical University, Almaty, Kazakhstan
Almaty, Kazakhstan
MA

Malika Alimussina, MD PhD

Senior Scientist
University of Glasgow, Glasgow, United Kingdom
Glasgow, United Kingdom
AN

Akmaral Nurbekova, MD

Pediatric Endocrinologist
Kazakh National Medical University, Almaty, Kazakhstan.
Almaty, Kazakhstan

Disclosure(s):

Svetlana Ten, MD: BioMarin: speaker ()

Background
Vosoritide (Voxzogo) improves growth in children with achondroplasia by counteracting FGFR3-mediated growth inhibition. However, growth response in clinical practice is variable, and the determinants of inadequate response remain incompletely understood. Identifying modifiable factors such as endocrine comorbidities and pubertal status is essential for optimizing treatment outcomes.
Methods
We analyzed 12-month height outcomes in 54 children with achondroplasia treated with vosoritide, categorizing response by annual growth rate and evaluating the impact of endocrine comorbidities.
Study Cohort
Retrospective chart analysis was performed on 54 children with genetically confirmed achondroplasia who were treated with Vosoritide (Voxzogo) and followed for 12 months. Baseline height was recorded, and growth velocity at 12 months of treatment was calculated from this data. 40 children were from Kazakhstan, and 14 were treated in the United States.
Results
Patients were stratified by the first 12 months of growth velocity (GV).
20 (37%) of children (6 ±3.3 yrs, 12 males, 8 females) had an excellent response to Vosoritide, with GV≥6.5 cm/year; the average ± SD of GV was 8.52 ± 2.5 cm/year.
12 (22%) of children (7.4 ±3.1 yrs, 6 males, 6 females) had a good response to Vosoritide, with GV of 5.5-6.5 cm/year and an average GV of 5.93 ± 0.2 cm/year.
16 (30%) of children (6.4 ±4.4 yrs, 3 males, 3 females) had a moderate response to Vosoritide with GV of 4.5-5.5 cm/year, and an average GV of 4.8 0.21.
6 (11%) of children (7.4 ± 2.6 yrs, 6 males, 8 females) had a poor response (same as untreated) to Vosoritide, with GV of < 4.5 cm/year. The average  SD of GV in this group was 3.1 1.07 cm/year.
Among the 6 patients with poor or minimal growth response. 1 patient had confirmed growth hormone deficiency with very low IGF-1 and IGFBP3 levels and will be started on GH therapy. 1 patient entered puberty at age 13, further limiting growth potential. Therefore, only 4 of 54 patients (7%) represented true biological poor responders to vosoritide therapy.
59% (32/54) achieved an excellent or good response (≥5.5 cm/year), and 89% (48/54) achieved clinically meaningful growth improvement (≥4.5 cm/year). The true poor-response rate after excluding endocrine confounders is 7%. Growth hormone deficiency significantly blunted the response in 1 patient and should be systematically screened when the growth response is suboptimal.
Conclusion
Daily CNP analog Vosoritide demonstrates robust efficacy in clinical settings in the majority of children with achondroplasia. Apparent non-response is attributable to coexisting endocrine disorders, particularly growth hormone deficiency and advanced pubertal status, rather than intrinsic resistance to therapy.

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