A new study has found that a common arthritis drug may help patients grow stronger muscles, offering hope to people with muscle loss problems.
The research, done by scientists at Newcastle University and The Newcastle upon Tyne Hospitals NHS Foundation Trust, was published in The Lancet Rheumatology.
The drug is called Tofacitinib, and it’s usually used to treat rheumatoid arthritis (RA). It belongs to a group of medicines known as JAK inhibitors, which help reduce inflammation in the body. In this study, 15 patients with RA took Tofacitinib for six months. During that time, their leg muscles—especially in the thigh—got bigger.
The condition these patients were facing is called sarcopenia. Sarcopenia is when people lose muscle mass and strength as they get older. It’s a serious issue that can lead to falls, bone breaks, physical disability, and even early death.
There are currently no approved drugs that can reverse sarcopenia, especially in people with long-term inflammation like RA.
This research project, called the RAMUS study (short for Rheumatoid Arthritis and MUScle), measured the size of the patients’ leg muscles using MRI scans. After six months, leg muscle volume had increased by about 4%, which is around 242 cubic centimeters. In the thigh area alone, the increase was about 5%.
The scientists also studied muscle tissue at the genetic level. They found that the gene activity in these muscles had changed in a way that was the opposite of what happens in aging muscles. This means that the drug might be reversing some of the harmful changes that happen naturally as we get older.
Dr. Joshua Bennett, the lead author of the study and a rheumatology specialist, said this was the first time a JAK inhibitor had shown a possible ability to reverse muscle loss in people with RA.
He explained that although this was a small study, it could lead to larger studies that test whether these drugs can help other people with sarcopenia—not just those with RA.
Most of the patients in the study—13 out of 15—did experience some side effects, but most of them were mild. The researchers say that bigger studies are needed, especially ones that include a comparison group that doesn’t take the drug, to better understand how well it works and how safe it is.
Professor John Isaacs, a senior researcher in the study, said that the findings support the idea that inflammation may be one of the main reasons people lose muscle. Since the drug reduced inflammation and led to more muscle growth, it suggests that fighting inflammation could help treat muscle-wasting diseases.
Even though the study didn’t show a clear improvement in muscle strength, this might be because people with arthritis have joint pain that makes it hard to perform strength tests.
So, the lack of strength improvement doesn’t mean the muscle growth isn’t helpful. Bigger and healthier muscles could still protect patients from falling, breaking bones, or becoming disabled.
In summary, this study gives early but exciting evidence that a medicine already used to treat arthritis might also help people grow back muscle lost due to aging or disease. More research is needed, but the results bring new hope to people living with sarcopenia.
If you care about pain, please read studies about how to manage your back pain, and Krill oil could improve muscle health in older people.
For more health information, please see recent studies about how to live pain-free with arthritis, and results showing common native American plant may help reduce diarrhea and pain.
The study is published in The Lancet Rheumatology.
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