Antimalarial Drug Shows Promise In Treating PCOS Symptoms

A roaring river flows past a stone-filled bank, where a delicate tower of rocks stands, balanced so precisely that even a small nudge could bring it crashing down. This fragile structure mirrors the human endocrine system, which relies on the careful balance of over 50 hormones. When this balance tips, it can lead to disorders like diabetes, obesity, and polycystic ovarian syndrome (PCOS).

PCOS affects 10–13% of women of reproductive age. Its symptoms include irregular periods, ovarian cysts, weight gain, insulin resistance, facial hair growth, and infertility. Current treatments, such as birth control pills and medications to control blood sugar, help manage some symptoms but do not address the root cause.

Recently, Qi-Qun Tang, a researcher at Fudan University Shanghai Medical College, discovered that compounds from antimalarial drugs—called artemisinins—could help treat PCOS. His team found that these compounds restore hormonal balance in both rodent models and human patients. “This is the first treatment that addresses almost all symptoms of PCOS,” said Tang. Their findings were published in the journal Science.

Elisabet Stener-Victorin, a reproductive endocrinologist at Karolinska Institute who was not part of the study, expressed surprise at the depth of the team’s approach. “How did they come up with this idea?” she wondered.

Tang’s interest in PCOS began during research on obesity. He found that artemisinin improved the function of brown fat, a type of fat that helps regulate body temperature and metabolism. Around the same time, another research group showed that brown fat is significantly reduced in rats with PCOS. When brown fat was transplanted into these rats, their symptoms improved. This led Tang to test if artemisinin could help treat PCOS.

His team began by creating a PCOS-like condition in mice using high levels of androgens, hormones such as testosterone that are elevated in PCOS. When they treated these mice with a derivative of artemisinin—artemether (ATM)—the results were striking. Testosterone levels dropped, the mice’s disrupted reproductive cycles normalized, and the number of ovarian cysts decreased. Even fertility improved, with treated mice having more successful pregnancies compared to those treated with contraceptive pills, which don’t improve ovarian health or fertility.

Next, the team investigated how ATM reduced testosterone. In female ovaries, enzymes convert cholesterol into androgens. Tang’s team found that ATM significantly reduced the levels of one key enzyme, CYP11A1. Treated cells produced less testosterone, confirming that this enzyme plays a central role. They observed the same effect in ATM-treated mice.

To understand why ATM reduced CYP11A1, the researchers found that it made the enzyme more unstable and easier to break down. They discovered that ATM boosted the interaction between CYP11A1 and another protein, LONP1, which helps degrade faulty proteins. By acting like a “molecular glue,” ATM strengthened this interaction, speeding up CYP11A1’s breakdown and lowering testosterone levels.

Earlier studies had shown that women with PCOS have more CYP11A1 and less LONP1 in their ovarian cells compared to women without PCOS. So, Tang’s team launched a small clinical trial involving 19 women with PCOS. After 12 weeks of oral artemisinin treatment, participants showed lower testosterone levels and improved ovarian health. Notably, 63% reported regular menstrual cycles by the end of the study.

Despite these promising results, Stener-Victorin emphasized the need for caution. “This was an uncontrolled study, so the placebo effect could be strong,” she said. “We need randomized, placebo-controlled trials before this can become a standard treatment.”