Swiss pharmaceutical company Roche scored a victory this week as the FDA granted its approval for a new treatment for hemophilia – but that approval came with a black box warning.

Hemophilia is a condition in which a person’s blood lacks particular clotting factors. Without treatment, even a small cut or bump can be fatal. Although the disease is passed down through the mother, most victims are male (one type, hemophilia C, can occur in girls as well as boys).

Among the more famous victims of hemophilia were descendants of 19th-Century British monarch Queen Victoria. Her own son, Prince Leopold, and her great-grandson Tsarvich Alexei Romanov, both suffered from the condition. Another prominent figure who suffered from hemophilia was Ryan White (1971-1990), an Indiana boy who wound up contracting AIDS from a blood transfusion.

Depending on the severity of the disease, patients are normally treated with clotting factors or clot-preserving medications and/or sealants. However, some who suffer from hemophilia A (the most common form of the disease) develop resistance to the clotting factor used to treat their condition. The new medication, known as Hemlibra (emicizumab), represents a novel treatment (first in its class) that is injected once per week, working with other clotting factors in the blood in order to promote clotting.

Roche has been dealing with the expiration of numerous patents and decline in sales. The introduction of Hemlibra is part of CEO Severin Schwan’s strategy to introduce new “blockbuster” medications in order to offset the reduced revenues as the company loses its exclusivity on older medications. According to chief medical officer Sandra Horning, Hemlibra “represents an important advancement for people with hemophilia A with inhibitors, who have struggled to manage their bleeding disorder and haven’t had a new medicine in nearly 20 years.”

Sales for Hemlibra are expected to total approximately $1.6 billion a year by 2022.

The downside is that some patients in the clinical trials developed thrombosis, or blood clots that put them at risk for stroke – hence the black box warning required by the FDA. This may slow its acceptance among physicians, who currently use medications produced by a rival company, U.K.-based Shire, a drug maker that has long specialized in treatments for rare diseases.

Currently, Roche is waiting on data from Hemlibra’s Phase III trials, which will determine the drug’s efficacy on patients who have not developed resistance to the clotting factor most commonly used to treat the disorder. A successful outcome could expand the market for what Roche hopes will be the next “breakthrough” treatment for hemophilia.

K.J. McElrath is a former history and social studies teacher who has long maintained a keen interest in legal and social issues. In addition to writing for The Ring of Fire, he is the author of two published novels: Tamanous Cooley, a darkly comic environmental twist on Dante's Inferno, and The Missionary's Wife, a story of the conflict between human nature and fundamentalist religious dogma. When not engaged in journalistic or literary pursuits, K.J. works as an entertainer and film composer.