Women and Men Differ, and It’s Affecting HIV Clinical Trials, Treatments and Cures

Women and Men Differ, and It’s Affecting HIV Clinical Trials, Treatments and Cures

Scientists are constantly looking for ways to cure HIV – the virus known to cause AIDS – on the heels of reports that another person has been cured of the disease. However, researchers must address the real issue thwarting their attempts – the lack of women in clinical trials for cures, treatments and vaccines.

There are women than men living with HIV around the world. In fact, more than half of the 35 million infections are found in women, and it’s the number one cause of death in reproductive-aged women. New infections in both Africa, South America and the southern U.S. are found in women and are continuing the epidemic.

However, how men and women respond to HIV infection is different, and clinical trials are primarily made up of gay men. Potential cure trials don’t do very well.

The AMFAR charity did an investigation in 2016, noting that women had 11 percent representation. Antiretroviral drug trials were a bit better, with 19 percent of those involved being women.

At 38 percent, vaccine studies were considered the closest in male/female equal participation.

AMFAR Director of Research Rowena Johnson said if a cure is to be found, it must work for everyone.

The medical community realizes that the immune system of men and women are different. For instance, the flu shot tends to elicit a more powerful immune response in women than in men. And, the way HIV infections respond to medication also different. For example, women’s immune system tends to respond forcefully, keeping control of the virus for up to seven years.

However, over time, this high alert can lead to women being diagnosed with AIDS much sooner than men infected with the virus, which can lead to more strokes and heart attacks.

University of California, San Francisco Professor of Medicine Dr. Monica Gandhi said there are all kinds of differences between the genders – perhaps because of the hormonal effects. For instance, estrogen may cause HIV to lie dormant, which makes it more difficult for drugs or the immune system to kill.

These differences could be seen even before children went through puberty. One study found that 10 of the 11 children noted as being as elite controllers – individuals who could suppress HIV to nearly untraceable levels – were girls.

On top of that, women don’t respond the same way as men to some drugs.

For instance, the drug Dolutegravir can cause neural tube defects in women who are using the drug. Nevirapine can cause severe rashes in women. And, despite all this evidence, men still make up most of the drug trial test subjects.

Due to these sex differences, it could hinder researchers in finding potential cures – many of them tied to boosting the immune system in killing HIV itself.

The number of straight and gay men has always exceeded women, especially in the beginning when the epidemic was seen more in gay men. Still, three decades later, these are the same individuals trying to get into clinical trials. Gay men have developed strong support networks that have allowed them to learn of clinical trials that need participants, which are often held in cities with high HIV rates.

However, HIV infected women are often isolated and don’t advocate for one another. Women usually need help with transportation or childcare and are often more comfortable with talking with female physicians – very few trials will accommodate these needs.

Women of color in clinical trials is a real problem due to the wariness they have from being exploited by researchers. And, scientists don’t know how to regain the trust – to give these individuals the information they need that won’t seem intrusive.

When scientists are able to enroll women in their clinical trials, the Food and Drug Administration imposes stricter guidelines due to their stringent rules on women of childbearing years. For that reason, the majority of researchers won’t enroll women, only getting information after the drug has been released to the market.

There has been a rise in the number of women for two recent long-acting antiretroviral drugs – that can be injected each month instead of being taken orally – 33 percent for one study and 23 percent in the second study. Due to the treatment frequency, the trials are a bit hit with the women with patients lining up outside the clinic to get into the trial.

Despite the difficulty of getting women involved with trials, 75 percent of HIV infected individuals are men.

Written by Mark Riegel, MD

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