OR21-06 Growth Response Of Oral LUM-201 In OraGrowtH210 And OraGrowtH212 Trials In Idiopathic Pediatric Growth Hormone Deficiency (iPGHD): Combined Analysis Interim Analysis Data Open Access

Disclosure: M.J. Tansey: Research Investigator; Self; Lumos Pharma, Inc. S.A. Bowden: Research Investigator; Self; Lumos Pharma, Inc. A.N. Dauber: Research Investigator; Self; Lumos Pharma, Inc. B. Wikiera: Research Investigator; Self; Lumos Pharma, Inc. B. Pyrzak: Research Investigator; Self; Lumos Pharma, Inc. A.T. Bossowski: Research Investigator; Self; Lumos Pharma, Inc. E. Petriczko: Research Investigator; Self; Lumos Pharma, Inc. R. Stawerska: Research Investigator; Self; Lumos Pharma, Inc. E. Moszczynska: Research Investigator; Self; Lumos Pharma, Inc. F. Cassorla: Research Investigator; Self; Lumos Pharma, Inc. Speaker; Self; Lumos Pharma, Inc. M.M. Feldt: Research Investigator; Self; Lumos Pharma, Inc. A.J. Lunsford: Research Investigator; Self; Lumos Pharma, Inc. M.E. Gottschalk: Research Investigator; Self; Lumos Pharma, Inc. M. Marin: Research Investigator; Self; Lumos Pharma, Inc. S.N. Nayak: Research Investigator; Self; Lumos Pharma, Inc. S. Bhuvana: Research Investigator; Self; Lumos Pharma, Inc. D.R. Repaske: Research Investigator; Self; Lumos Pharma, Inc. L.A. Soyka: Research Investigator; Self; Lumos Pharma, Inc. J.S. Fuqua: Research Investigator; Self; Lumos Pharma, Inc. O. Escobar: Research Investigator; Self; Lumos Pharma, Inc. D.A. Bowlby: Research Investigator; Self; Lumos Pharma, Inc. P.Y. Fechner: Research Investigator; Self; Lumos Pharma, Inc. E. Wiltshire: Research Investigator; Self; Lumos Pharma, Inc. M. Harris: Research Investigator; Self; Lumos Pharma, Inc. K.A. Wintergerst: Research Investigator; Self; Lumos Pharma, Inc. A.R. Lafferty: Research Investigator; Self; Lumos Pharma, Inc. B.S. Miller: Research Investigator; Self; Lumos Pharma, Inc. P. Simm: Research Investigator; Self; Lumos Pharma, Inc. A. Bruchey: Employee; Self; Lumos Pharma, Inc. Stock Owner; Self; Lumos Pharma, Inc. C. Smith: Employee; Self; Lumos Pharma, Inc. Stock Owner; Self; Lumos Pharma, Inc. D.B. Karpf: Employee; Self; Lumos Pharma, Inc. Stock Owner; Self; Lumos Pharma, Inc. J.C. McKew: Employee; Self; Lumos Pharma, Inc. Stock Owner; Self; Lumos Pharma, Inc. M.O. Thorner: Consulting Fee; Self; Lumos Pharma, Inc. Stock Owner; Self; Lumos Pharma, Inc.

Background: LUM-201 (ibutamoren), a growth hormone (GH) secretagogue receptor 1a (GHSR1a) agonist, is a potent, long-acting investigational oral GH secretagogue currently studied in three Idiopathic Pediatric GH Deficiency (iPGHD) studies. The LUM-201 predictive enrichment marker (PEM) is used to identify patients diagnosed with iPGHD (peak stimulated GH >3<10 ng/mL) who are likely to respond to LUM-201. PEM positivity is defined as a baseline insulin-like growth factor-1 (IGF-1) level >30 ng/mL and a peak GH of ≥5 ng/mL in response to a single 0.8 mg/kg dose of LUM-201. Objectives: Report the growth response analyzing the combined interim analysis (IA) data from two Phase 2 trials studying LUM-201 at two different doses (1.6 mg/kg/day or 3.2 mg/kg/day). Methods: IA data from both studies were combined and analyzed for calculated annualized height velocity (AHV). Baseline demographics were analyzed for the two combined cohorts. Results: After 6 months of treatment with LUM-201, the calculated AHV (mean ±SD ) was 8.1±1.9 cm/year in the 1.6 mg/kg/day group and 8.0±1.5 cm/year in the 3.2 mg/kg/day group (N=15 in both groups). After 9 months of treatment, the calculated AHV was 7.8±1.7 cm/year in the 1.6 mg/kg/day group and 7.3±1.7 cm/year in the 3.2 mg/kg/day group (N=10 in both groups). After 12 months of treatment, the calculated AHV was 7.8±1.7 cm/year in the 1.6 mg/kg/day group and 7.4 ±1.2 cm/year in the 3.2 mg/kg/day group (N=6 in both groups). LUM-201 was well tolerated; no safety concerns were identified across the dose range in adverse events (AE) data, laboratory values, and ECG values. Conclusions: As the growth velocity was comparable for the two doses of oral LUM-201, this analysis of the combined IA data appears to strongly support 1.6 mg/kg/day as the optimal dose for the Phase 3 trial, as doubling the dose appeared to offer no meaningful improvement in efficacy. Final determination will await final full data set analysis of both studies.

Presentation: Saturday, June 17, 2023