FDA needs better data to treat women and chronic pain

Recent hopes of a new treatment for a common chronic pain condition, osteoarthritis (OA), were dashed when a much-anticipated novel OA pain drug was not approved by the FDA’s expert panel because of safety concerns. Currently, there is no targeted therapy for this condition and most patients manage it by using either NSAIDS or opioids and joint replacement surgery when worsening of the joint occurs.

OA, a degenerative chronic pain condition, disproportionately affects women — and its symptoms are more severe in women. Research over the years has well documented these sex and gender differences with regard to prevalence, incidence and severity of this disease in knee and hips. This includes women being more likely to undergo knee or hip arthroplasty compared to men.

In addition to these sex differences in OA, women are also two to three times more likely to have chronic overlapping conditions than men. OA and other chronic pain conditions are often debilitating, and given the limitations in current treatment options, women need to know how the safety data for any potential treatments impact them in particular.

Women were the majority of participants in the clinical trials (65 percent to 67 percent) for this OA treatment. This is important to note because women have consistently been underrepresented in dual gender trials for the past 30 years, since the NIH Revitalization Act of 1993 made it possible for women to be included in clinical trials at all.

These trials also included participants from diverse races (white, Black and Asian) based on the OA representation in the general population. Women of color are disproportionately affected by OA, and socioeconomic factors can contribute to worsening of symptoms.

Despite the inclusion of women and diverse races in the trials, adverse events and safety issues were not reported by demographic subgroups. This is essential information to examine since women as a rule experience more side effects and adverse events from taking medications compared to men. Sometimes these events are so severe that there is more risk than benefit, and women may not be able to use a certain medication at all. Women also may require a different dosing level than men. From 1997 to 2001, eight out of ten drugs were withdrawn from the market because they posed greater health risks to women.

Additionally, in 2013, the FDA recommended lowering the dose of zolpidem by half for women (10 mg to 5 mg) as women were shown to metabolize the same dose more slowly than men, resulting in a 50 percent higher serum level. In spite of this, recent studies on zolpidem have indicated that a higher dose was still being taken by women (68 percent), particularly older women. This suggests that policy change has not modified the prescribing habits of physicians, which exemplifies how critical it is to evaluate sex differences in side effects and adverse events at the time of drug approval and during the different phases of a clinical trial, before it’s in widespread use.

It’s important that the FDA require manufacturers to not just collect demographic data (sex, age, race and ethnicity) in clinical trials but to actually determine the effect of the treatment for the different subgroups and report such information, first by sex and then followed by age and then race/ethnicity to get a full understanding of subgroup-specific treatment effects.

Advocacy groups have tirelessly advocated for the FDA to collect and analyze data by sex, race, ethnicity and age when evaluating drugs for approval and to make this information accessible to the public. Clinically meaningful information, such as how well a treatment is likely to work for an individual or a subgroup of individuals and any similarities or differences in response among different subgroups, benefits patients and can be used by healthcare providers to tailor a patient’s treatment to their needs.

Since multiple factors influence the treatment of chronic pain, new treatments need to allow for an individualized approach that takes into account the biology, psychology and social factors in patients’ lives. This will ensure that health care providers have several treatment options available for their diverse patient populations.

Innovation is important for diseases like OA and other chronic pain conditions that affect women to an incredible extent, especially where treatment options are limited. Evaluating adverse events is an important step in knowing whether a badly needed proposed treatment has real benefit to a patient.

Novel treatments, especially for osteoarthritis. have the potential to allow women who are often juggling work, family and caregiving to remain active while living with debilitating chronic pain. We hope that novel innovative treatments will also make chronic pain management affordable and accessible to more women.

But first we need to know that they’re safe.

Monica Mallampalli, Ph.D., is the senior advisor, Scientific & Strategic Initiatives at HealthyWomen.org, which aims to educate women ages 35 to 64 to make informed health choices.

Martha Nolan is senior policy advisor at HealthyWomen.org.