Approval of Fulyzaq (Crofelemer) to Relieve Symptoms of Diarrhea in HIV/AIDS Patients Taking Antiretroviral Therapy

On December 31, 2012, FDA approved Fulyzaq (crofelemer) to relieve symptoms of diarrhea in HIV/AIDS patients taking combination antiretroviral therapy. The recommended dose is one 125 mg delayed-release tablet taken orally two times a day, with or without food. Fulyzaq tablets should not be crushed or chewed. Tablets should be swallowed whole.

Diarrhea is experienced by many HIV/AIDS patients and is a common reason why patients discontinue or switch their antiretroviral therapies. Fulyzaq is indicated in HIV/AIDS patients whose diarrhea is not caused by an infection from a virus, bacteria, or parasite. Patients take Fulyzaq two times a day to manage watery diarrhea due to the secretion of electrolytes and water in the gastrointestinal tract.

The safety and efficacy of Fulyzaq were established in placebo-controlled trials.

Of 374 HIV-positive patients on stable antiretroviral therapy with a history of diarrhea lasting one month or longer, the median number of daily watery bowel movements was 2.5 per day. Patients who had diarrhea caused by an infection or a gastrointestinal disease were excluded from participating in the trials. Patients were randomly assigned to take Fulyzaq or a placebo twice daily.

The trial was designed to measure clinical response, defined as the number of patients who had two or fewer watery bowel movements weekly. Results showed that 17.6 percent of patients taking Fulyzaq experienced clinical response compared with 8 percent taking placebo. In some patients, a persistent anti-diarrheal effect was seen for 20 weeks.

No dose modifications are recommended with respect to CD4 cell count and HIV viral load, based on the findings in subgroups of patients defined by CD4 cell count and HIV viral load.

Among race subgroups, there were no differences in the consistency of the crofelemer treatment effect except for the subgroup of African-Americans; crofelemer was less effective in African-Americans than non-African-Americans.

The safety and effectiveness of Fulyzaq have not been established in pediatric patients less than 18 years of age.

Before treating patients with Fulyzaq, health care professionals should conduct proper testing to confirm the diarrhea is not caused by an infection or a gastrointestinal disease. If infectious etiologies are not considered, and Fulyzaq is initiated based on a presumptive diagnosis of non-infectious diarrhea, then there is a risk that patients with infectious etiologies will not receive the appropriate treatments, and their disease may worsen.

Common side effects reported in patients taking Fulyzaq in the clinical trial were upper respiratory tract infection, bronchitis, cough, flatulence, and increased levels of the liver enzyme bilirubin.

The product label for Fulyzaq can be found at Drugs@FDA.

Derived from the red sap of the Croton lechleri plant, Fulyzaq is the second botanical prescription drug approved by FDA. A botanical drug product is often a complex mixture derived from one or more plant materials with varying degrees of purification. (In 2006, the FDA approved the first botanical prescription drug, Veregen (sinecatechins), a treatment for external genital and perianal warts.)

As with other drugs, the safety and efficacy of a botanical drug product must be established through clinical trials. In addition, manufacturers of a botanical drug product must ensure rigorous control of raw materials, and good agricultural and collection practices, together with analytical testing of the final product.

Fulyzaq is distributed by Salix Pharmaceuticals, based in Raleigh, N.C. under license from Napo Pharmaceuticals, Inc. and is marketed by PharmaDerm, of Florham Park, N.J.