Bimagrumab to improve recovery after hip fracture in older adults: a multicentre, double-blind, randomised, parallel-group, placebo-controlled, phase 2a/b trial.

BACKGROUND

Older adult patients (ie, those aged ≥60 years) undergoing surgery for hip fracture repair frequently experience loss of muscle mass and strength due to poor mobility and delayed functional recovery. No proven treatment is currently available to enhance recovery of physical function in this growing patient population. This study aimed to investigate whether bimagrumab, a human monoclonal antibody targeting activin type 2 receptors, can improve post-surgical recovery.

METHODS

This multicentre, double-blind, randomised, parallel-group, placebo-controlled, phase 2a/b trial was done at 50 clinical research centres in 18 countries. Participants aged 60 years or older with a body-mass index of 15-35 kg/m

FINDINGS

Between Sept 16, 2014, and Dec 15, 2017, 384 patients were screened, of whom 250 patients were enrolled and randomly assigned to the placebo group (n=72), the bimagrumab 70 mg group (n=34), the bimagrumab 210 mg group (n=69), or the bimagrumab 700 mg group (n=75). A total of 207 (83%) participants completed the 24-week treatment period. There was a significant absolute increase in lean body mass from baseline compared with placebo (0·2 kg [SD 2·0]) in the bimagrumab 210 mg group (1·9 kg [1·7]; p<0·0001) and in the bimagrumab 700 mg group 2·8 kg [2·2]; p<0·0001) but not in the bimagrumab 70 mg group (0·6 kg [SD 2·2]; significance not assessed). Changes in habitual gait speed and short physical performance battery scores between baseline and week 24 were not significantly different across the treatment groups, suggesting no enhancement of physical recovery with bimagrumab over placebo. Bimagrumab was safe and well tolerated. The most frequently reported treatment-emergent adverse events were falls (six [18%] of 34 participants in the bimagrumab 70 mg group; 12 [17%] of 69 participants in the bimagrumab 210 mg group; 14 [19%] of 75 participants in the bimagrumab 700 mg group; and 13 [18%] of 72 participants in the placebo group), muscle spasms (two [6%] in the bimagrumab 70 mg group; 17 [25%] in the bimagrumab 210 mg group; 12 [16%] in the bimagrumab 700 mg group; and six [8%] in the placebo group), and arthralgia (five [15%] in the bimagrumab 70 mg group; six [9%] in the bimagrumab 210 mg group; nine [12%] in the bimagrumab 700 mg group; and five [7%] in the placebo group). Six deaths were reported during the study, none of which were considered by investigators as related to the study drug.

INTERPRETATION

Bimagrumab treatment for 24 weeks led to dose-dependent, significant increases in lean body mass in older patients recovering from hip fracture surgery when compared with placebo. However, no functional benefit was observed in recovery of mobility or lower extremity function following bimagrumab treatment compared with placebo.

FUNDING

Novartis Pharma.

Informations de copyright

Copyright © 2021 The Authors. Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Published by Elsevier Ltd.. All rights reserved.

Déclaration de conflit d'intérêts

Declaration of interests LCH reports grants for clinical trials from Alexion, Amgen, Ascendis, Novartis, and Shire; and honoraria for participation in advisory boards for Amgen, Alexion, Shire, KKI, and UCB. LZA and LBT were employees of Novartis during the course of this study and own stocks in Novartis. CR has done studies for Novartis, Amgen, Roche, Eli Lilly, and CytoDyn. MC, DR, MA, NF, AAS-T, and DAP are employees of and own stock in Novartis. RW, ZV, and NS declare no competing interests.