The Food and Drug Administration issued an untitled letter to Ascend Therapeutics for claims made in its EstroGel promotions.

The offending promotional material was a sell sheet distributed to healthcare professionals. As per the FDA, the sheet’s claim that EstroGel had the “lowest effective dose” of estradiol, an estrogen steroid hormone, was misleading, since there are other products that have doses lower than EstroGel’s.

Moreover, the sell sheet implies that lower doses of estradiol than that contained in EstroGel are ineffective, a claim which neither of two studies Ascend references in its sell sheet can support.

The Aug. 16 letter was the second such enforcement action related to the brand. Ascend received an untitled letter for EstroGel in June 2015 for omitting risk information on a card distributed to HCPs.

EstroGel is approved to treat some moderate-to-severe symptoms of menopause, including hot flashes and vaginal itching and dryness. The treatment was originally cleared for marketing in 2004. EstroGel is Ascend’s only approved product.

Among other claims the agency said are false or misleading, the sell sheet infers that EstroGel has an endorsement from the North American Menopause Society, which recommends first-line treatment of vasomotor symptoms with the lowest effective dose.

The letter, issued by the FDA’s Office of Prescription Drug Promotion (OPDP), requested that Ascend immediately stop distributing the sell sheet and any other promotional materials that have similar misleading claims. Ascend has until August 30 to respond.

Representatives for Ascend did not immediately respond to a request for comment.

This is the fourth letter from the OPDP this year, following others sent to Pfizer, Arog Pharmaceuticals, and Collegium Pharmaceuticals.