(The Hill) — The Food and Drug Administration (FDA) is pulling its approval of the only drug on the market for reducing the risk of preterm birth in pregnant women, citing a lack of effectiveness demonstrated by the treatment.

The FDA approved Makena in 2011 under its accelerated approval pathway as a treatment for reducing the risk of preterm birth in women pregnant with one child and who have a history of spontaneous preterm birth.

At the time of the approval, the FDA stipulated that a confirmatory study be conducted following approval. This study subsequently failed to confirm clinical benefits of Makena in reducing the risk of preterm births.

The FDA’s Center for Drug Evaluation and Research proposed in 2020 that Makena be withdrawn from the market as a result of the study. Covis Pharma, the maker of Makena, moved to voluntarily withdraw the product after a key advisory committee recommended its removal from the market last month.

Covis Chief Innovation Officer Raghav Chari said his company stood by the “favorable benefit-risk profile” of the drug, but added that they would work with federal regulators to carry out an “orderly wind-down.”

There are no approved treatments for preterm birth.

“It is tragic that the scientific research and medical communities have not yet found a treatment shown to be effective in preventing preterm birth and improving neonatal outcomes—particularly in light of the fact that this serious condition has a disparate impact on communities of color, especially Black women,” FDA Commissioner Robert Califf said in a statement.

The FDA noted that supplies of Makena have already been distributed throughout the U.S. and advised that patients speak with their physicians.