FDA Approves Zorvolex for the Treatment of Osteoarthritis Pain

Clinicians who treat patients suffering with osteoarthritis pain have a new low-dose nonsteroidal anti-inflammatory drug (NSAID) option at their disposal.

Iroko Pharmaceuticals, LLC, announced today the United States Food and Drug Administration (FDA) has approved Zorvolex (diclofenac) capsules for the management of osteoarthritis pain. Zorvolex had previously been approved for the treatment of mild to moderate acute pain in adults.

According to a news release from Iroko, Zorvolex “was developed to align with recommendations from FDA and several professional medical organizations that NSAIDs be used at the lowest effective dose for the shortest possible duration consistent with individual patient treatment goals.”

Zorvolex is formulated with submicron particles of diclofenac, which Iroko says “provides an increased surface area, leading to faster dissolution.” The submicron particles of diclofenac in Zorvolex are approximately 20 times smaller than their original size and were developed using proprietary SoluMatrix Fine Particle Technology™, making Zorvolex the first FDA-approved low dose NSAID developed using this technology.

As with all NSAIDs, Zorvolex is associated with increased risk of potentially serious cardiovascular and gastrointestinal adverse events. The boxed warning and Safety Information for Zorvolex notes that NSAIDs “may cause an increased risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, which can be fatal. This risk may increase with duration of use. Patients with cardiovascular disease or risk factors for cardiovascular disease may be at greater risk.” The boxed warning also notes that NSAIDs “cause an increased risk of serious gastrointestinal adverse events including bleeding, ulceration, and perforation of the stomach or intestines, which can be fatal. These events can occur at any time during use and without warning symptoms. Elderly patients are at greater rg

These warnings are included as per FDA guidance released several years ago asking all manufacturers of NSAIDs to include labeling information that highlights “the potential for increased risk of cardiovascular (CV) events with these drugs and the well-described, serious, and potentially life-threatening gastrointestinal (GI) bleeding associated with their use.”

The FDA guidance also encouraged practitioners who prescribe NSAIDs to “use the lowest effective dose for the shortest duration consistent with individual patient treatment goals.”

The approval of Zorvolex for the management of osteoarthritis pain was “supported by data from a 12-week, multi-center, randomized, double-blind, parallel-group, placebo-controlled trial that enrolled 305 patients, aged 41-90 years, with osteoarthritis of the hip or knee. Half of the patients were between the ages of 61-90,” according to the news release. In the study, participants were randomized to receive Zorvolex 35 mg three times daily (tid) or 35 mg twice daily (bid), or placebo.

According to the study results, which were published in Current Medical Research and Opinion, participants had clinically and radiographically confirmed hip or knee osteoarthritis (OA) and “were chronic NSAID and/or acetaminophen (APAP) users with baseline Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) pain subscale scores ≥40 mm by visual analog scale and an OA flare (≥15 mm increase in WOMAC pain subscale score following discontinuation of NSAIDs/APAP at screening).”

The authors reported that treatment with Zorvolex 35 mg tid “significantly improved WOMAC pain subscale scores from baseline at 12 weeks (−44.1; p = 0.0024) compared with placebo (−32.5).” Although treatment with Zorvolex 35 mg bid “provided numerical improvement in pain at week 12” compared with placebo, the results did not reach statistical significance.

Treatment with Zorvolex 35 mg tid (−35.9; p = 0.0002) and 35 mg bid (−30.3; p = 0.0363) “improved the average total WOMAC score in treated patients over 12 weeks compared with placebo (−23.2).” The most frequently reported adverse events in the patients treated with Zorvolex were diarrhea, headache, nausea, and constipation.

Based on these results, the study authors concluded that Zorvolex is an effective therapeutic option for the treatment of patients suffering with osteoarthritis pain.

Roy Altman, MD, Professor of Medicine in Rheumatology at UCLA, said in the news release that “NSAIDs continue to be an integral part of the management for osteoarthritis, the most common type of arthritis, and their use is likely to increase as the US population continues to age and the incidence of osteoarthritis rises… the approval of Zorvolex is a welcome and meaningful advance.”

See the full Prescribing Information for Zorvolex for additional important safety and dosing information. An NSAID Medication Guide is also available.