What Is Bimagrumab?
Bimagrumab is a drug that has been studied in 11 clinical trials involving a total of 2,047 participants. It is a human monoclonal antibody designed to target the activin receptor type II. By blocking this receptor, bimagrumab aims to promote muscle growth and reduce fat mass. This mechanism suggests its potential use in conditions where muscle wasting is a concern or where an increase in muscle mass and reduction in fat could be beneficial.
The first clinical trial for bimagrumab began in 2013, and the latest trial is expected to conclude in 2025. While specific FDA approvals are not detailed in the provided data, bimagrumab has been investigated for a range of conditions, primarily focusing on muscle-related disorders and metabolic conditions.
Uses and Conditions Under Study
Bimagrumab has been investigated across several conditions, with a primary focus on muscle health and metabolic disorders. Its mechanism of action, which involves promoting muscle growth and reducing fat, makes it a candidate for these areas.
- Obesity and Overweight: Bimagrumab has been studied in 8 trials for conditions including Obesity, Overweight, Obese, and Overweight or Obesity. These trials explore whether the drug can help individuals manage their weight by increasing muscle mass and decreasing fat, which are key factors in body composition and metabolic health.
- Muscle Wasting Conditions: The drug has been evaluated in 6 trials for conditions characterized by muscle loss and weakness. These include Sarcopenia, Sporadic Inclusion Body Myositis (sIBM), and Muscle Wasting (Atrophy) After Hip Fracture Surgery. For patients with these conditions, bimagrumab's ability to promote muscle growth could potentially improve strength and physical function.
- Healthy Participants: One trial involved healthy participants. Studies in healthy individuals are typically conducted to understand how a drug is absorbed, distributed, metabolized, and excreted by the body, as well as to assess its safety profile before widespread use in patient populations.
Dosing
Bimagrumab has been studied in various forms and dosages across its clinical trials. It has been administered as a subcutaneous (SC or SQ) injection, meaning it is given under the skin, and also as an intravenous (i.v.) infusion, delivered directly into a vein. One common subcutaneous regimen studied was 300 mg weekly.
Different strengths of bimagrumab have been investigated, including doses based on body weight, such as 1 mg/kg, 3 mg/kg, 10 mg/kg, and 30 mg/kg. Fixed doses like 70 mg, 210 mg, and 700 mg have also been explored. The drug has been studied both as a standalone treatment and in combination with other medications, such as tirzepatide and semaglutide, with various coadministration and coformulation strategies. For intravenous administration, a 150 mg/mL concentrate for solution was used. The specific dose and administration route depend on the condition being studied and the trial design.
Side Effects
In clinical trials, patients taking Bimagrumab experienced certain side effects more frequently than those taking a placebo. The most common side effects reported were:
- Muscle spasms: 27.7% of patients taking Bimagrumab experienced muscle spasms, compared to 7.4% on placebo. In one specific trial, 52.9% of those on Bimagrumab reported muscle spasms, compared to 21.0% on placebo.
- Diarrhea: 24.4% of patients on Bimagrumab reported diarrhea, compared to 14.2% on placebo.
- Fall: 24.0% of patients on Bimagrumab experienced a fall, compared to 18.4% on placebo.
- Nausea: 23.6% of patients on Bimagrumab reported nausea, compared to 18.9% on placebo.
- Acne: 21.5% of patients on Bimagrumab developed acne, compared to 4.9% on placebo.
Other side effects reported more frequently with Bimagrumab compared to placebo included contusion (6.5% vs. 5.1%) and back pain (5.2% vs. 3.7%).
Some side effects occurred at similar or slightly lower rates in patients taking Bimagrumab compared to placebo, such as
Currently Recruiting Trials
Bimagrumab is currently being investigated in new clinical trials, offering patients an opportunity to contribute to medical research. These studies aim to understand how Bimagrumab might help with conditions like obesity, focusing on specific aspects of body health.
One such study, NCT05933499, is a Phase 2 trial sponsored by Massachusetts General Hospital. This study is exploring the "Effect of Tirzepatide and Bimagrumab on Body Composition, Insulin Sensitivity, and Bone in Adults With Obesity." Researchers are particularly interested in how weight loss treatments can be improved. While losing weight is often beneficial, it can sometimes lead to an unintended loss of muscle mass and bone density, which might reduce the overall health benefits, such as improvements in glucose and insulin levels. This trial seeks to determine if a combination of Tirzepatide and Bimagrumab, or Bimagrumab alone, can help adults with obesity achieve weight loss that primarily consists of fat, while preserving valuable muscle and bone. The study is designed to enroll 63 participants and involves different treatment arms: Tirzepatide combined with bimagrumab, Tirzepatide with a placebo, or Bimagrumab with a placebo.
Where to Participate
Participation in the currently recruiting Bimagrumab clinical trials is focused on a single location at this time. This allows for concentrated research efforts and specialized care for participants.
The primary site for the recruiting study NCT05933499 is located in Boston, Massachusetts. Potential participants for this study must meet specific criteria. Eligibility requires individuals to be 18 years old. The study is open to participants of all genders. It is important to note that this trial is not seeking healthy volunteers; instead, it is designed for adults with obesity who are seeking treatment. Children are not eligible to participate in this particular study.
Development Timeline
The journey of Bimagrumab in clinical development began on August 19, 2013, marking the start of its exploration as a potential therapeutic agent. Initially, the drug's potential was investigated for conditions such as Irritable Bowel Syndrome with Constipation (IBS-C) and hyperphosphatemia. However, over time, the focus of research expanded significantly.
Key sponsors have driven Bimagrumab's development, including Novartis Pharmaceuticals, which has sponsored six trials, and Eli Lilly and Company, sponsoring four trials. Massachusetts General Hospital has also contributed by sponsoring one trial. The development pipeline broadened to include a range of conditions, particularly those involving muscle health and metabolism, such as Sporadic Inclusion Body Myositis (sIBM), muscle wasting after hip fracture surgery, and various stages of overweight and obesity.
Across its development, Bimagrumab has been studied in a total of 11 trials, enrolling 2,047 participants. These studies have progressed through various phases:
- One Phase 1 trial
- Seven Phase 2 trials
- Two Phase 2/Phase 3 trials
- One Phase 3 trial
This progression reflects a comprehensive evaluation of Bimagrumab's safety and efficacy across different patient populations and conditions, with the latest trial projected to conclude by March 28, 2025.