Mayne Pharma is in trouble with the FDA. The agency has accused the Australian pharma of giving a misleading impression of the risks of its oral birth control pill in a presentation, triggering an untitled letter (PDF).
FDA officials sent the letter after reviewing a slide deck (PDF) about Mayne’s contraceptive medication Nextstellis. The FDA claimed the presentation minimized the risks associated with Nextstellis and misrepresented how the drug compares to rival estrogen-containing combined hormonal contraceptives. Those failings are particularly concerning, according to the agency, because Nextstellis is linked to potentially life-threatening risks.
The FDA said the deck contains “misleading” claims that estetrol, one of the active ingredients in Nextstellis, is unique and intrinsically different from other estrogens. For example, claims that estetrol is “low impact” and has “minimal effect on the liver” suggest Nextstellis is safer than other estrogen-containing oral contraceptives, the FDA said, but that has “not been demonstrated.”
Sections of the deck deal specifically with the effect of Nextstellis on breast and liver tissue. One slide compares the “slow, extensive” hepatic metabolism of ethinyl estradiol, another estrogen commonly used in birth control pills, to the “minimal” hepatic metabolism of estetrol. The FDA said the slide misleadingly suggests estetrol has safety advantages over ethinyl estradiol.
Other slides say estetrol has “a low impact on breast tissue” and “does not stimulate breast tissue.” The FDA said the slides add to the misleading impression about the comparative safety of Nextstellis and rival oral contraceptives.
“These claims suggest that Nextstellis is a safer option for patients who have or have had breast cancer when, in fact, Nextstellis is contraindicated in patients with a current diagnosis or history of breast cancer, which may be sensitive to female hormones,” the FDA said.
The FDA sent the untitled letter on April 28 and gave Mayne 15 working days to respond in writing.
Mayne did not immediately respond to Fierce Pharma Marketing’s request for comment.
Nextstellis has been approved in the U.S. since 2021, when its estetrol became the first new estrogen introduced in the country in over half a century, per the company. Just a week before the FDA sent the letter, in an April 22 business update, Mayne reported (PDF) lower-than-expected volumes of Nextstellis, even as net sales for its overall women’s health segment grew 8% year over year.
Cosette Pharmaceuticals agreed to buy Mayne for $430 million in February. Cosette satisfied (PDF) one of the takeover closing conditions last week, keeping it on track to complete the deal in June or July.