Rheum Round-up: Amgen’s Court Victory, Cannabis in TKA Patients, and More

Here are the top stories covered by DocWire News this week in the Rheumatology section. In this edition, read about Amgen’s latest legal win, the effects of cannabis in knee replacement patients, how oophorectomy may impact bone health, and mental health risks associated with combined cannabis and opioid use to treat pain.

A U.S. judge ruled in favor of Amgen on the validity of two patents pertaining to the company’s drug Enbrel (etanercept), indicated for the treatment of rheumatic conditions including rheumatoid arthritis. Amgen was in a battle with Sandoz, a subsidiary of Novartis, which in 2016 received approval from the Food and Drug Administration (FDA) for a biosimilar of Amgen’s drug. However, Sandoz has not been able to market its drug, Erelzi, because of Amgen’s extended patent protection. The active ingredient in Enbrel is patent-protected until 2029. Enbrel earned FDA approval in 1998. The drug was manufactured by Immunex Corporation, which Amgen acquired several years after Enbrel was approved. Sandoz plans to appeal the ruling.

The use of cannabis may not affect short-term outcomes—positively or adversely—in total knee arthroplasty (TKA) patients, according to a new retrospective study. The single-center study, conducted between January 2014 and February 2018, included a total of 71 primary TKA patients who had at least one year of follow-up. Patient cannabis use was self-reported. Factors including length of stay, in-hospital total morphine equivalents, postoperative range of motion, Knee Society Score, and Veterans RAND-12 mental and physical component scores did not significantly differ between cannabis users and nonusers. There were five readmissions and five reoperations among users, and four readmissions and two reoperations among nonusers.

According to a new retrospective, cohort study, women who undergo oophorectomy as a preventative cancer measure may be susceptible to postoperative bone loss. The study included patients who underwent oophorectomy through the University Health Network, Toronto, Ontario, Canada, between January 2000 and May 2013. The primary outcome was annual change in bone mineral density (BMD) from baseline to follow-up in the lumbar spine, femoral neck, and total hip. Women who were premenopausal at the time of operation had a decrease in BMD from baseline to follow-up in all three anatomical locations. Women who were postmenopausal at the time of operation also had a significant decrease in BMD at the lumbar spine and femoral neck, but not at the total hip.

Patients with chronic pain using opioids and cannabis may be more likely to have symptoms of anxiety and depression compared to patients using opioids alone. The study included 450 adults in the U.S. with moderate to severe pain for longer than three months. The adults reported on their use of opioids and cannabis as well as anxiety and depression symptoms and their tobacco, alcohol, cocaine, and sedative use. Results were compared between patients taking opioids alone versus those who added cannabis. Although some outcomes were different between the two cohorts, pain was not one of them, according to the study’s abstract: “Results suggest that, compared to opioid use alone, opioid and cannabis co-use was associated with elevated anxiety and depression symptoms, as well as tobacco, alcohol, cocaine, and sedative use problems, but not pain experience.”

Kaitlyn D’Onofrio is a digital medical writer. She is interested in musculoskeletal health, the effect of exercise on health, and mental health awareness. When she’s not writing for DocWire, Kaitlyn is teaching yoga classes in her community, promoting wellness to her students.