Results from a 36-Week Open-Label Study of Recombinant Human Growth Hormone and Testosterone in Facioscapulohumeral Muscular Dystrophy (FSHD)
Chad Heatwole1, Elizabeth Luebbe1, Johanna Hamel1, Philip Mongiovi1, Emma Ciafaloni1, Nuran Dilek1, William Martens1, David Weber2, Rashid Hani1, Jamie Allen1, Claire Smith1, Samantha Howell1, Spencer Rosero1, Katy Eichinger1, Linday Baker1, Jeanne Dekdebrun1, Jim Hilbert1, Anika Varma1, Michael McDermott1, Charles Thornton1, Richard Moxley1
1University of Rochester Medical Center, 2Children's Hospital of Philadelphia
Objective:
To determine the safety and tolerability of daily recombinant human growth hormone (rHGH) combined with testosterone injections every 2 weeks in ambulatory men with FSHD.
Background:
FSHD is a progressive muscular dystrophy that affects ~4/100,000 people globally. Clinically, FSHD causes progressive weakness, muscle atrophy, and limitations with ambulation. A treatment that limits disease progression and/or reverses functional decline would be beneficial to this population.
Design/Methods:
We conducted a single center (University of Rochester), single-arm, proof-of-concept study to evaluate the safety and tolerability of daily rHGH (Genotropin®) combined with testosterone enanthate injections every 2 weeks in men with FSHD. Participants received study drugs for 24 weeks followed by a 12-week washout period. Participants received serial safety testing, laboratory testing, functional assessments, and disease burden monitoring during the study.
Results:
Nineteen out of 20 participants completed the study, with no participants experiencing a serious adverse event. One participant dropped out due to travel distance and the COVID pandemic. The most common adverse event was soreness at the rHGH/testosterone injection site (6 participants). After 24 weeks, the six-minute walk distance increased by 37.3 meters (p=0.0007), lean body mass improved by 2.2 kg (p<0.0001), body fat reduced by 1.3 kg (p=0.04), overall strength (standardized QMT, average % of predicted normal) increased by 3% (p=0.03), and total disease burden (FSHD-HI) reduced by 19% (6 points; p=0.04) from baseline.
Conclusions:
Combination therapy is safe and well-tolerated in men with FSHD. Despite FSHD being a progressive disease, participants experienced improvements in ambulation, strength, muscle mass, and disease burden in response to this study intervention. Placebo-controlled trials are needed to further investigate this promising therapeutic approach.