NAPO TO STUDY TREATMENT FOR HIV-ASSOCIATED DIARRHEA

Napo Pharmaceuticals has received independent review board (IRB) approval to begin the pivotal, Phase III ADVENT study of crofelemer for diarrhea in people living with HIV/AIDS, the company announced.

The ADVENT trial is a randomized, double-blind, parallel-group, placebo-controlled, two-stage, adaptive-design study to assess the efficacy and safety of crofelemer in doses of 125, 250 and 500 mg twice daily for the treatment of HIV-associated diarrhea. Napo met with the FDA in January under the special protocol assessment process to devise the adaptive design plan for the trial.

The trial will be executed in two stages, with Stage I representing a dose-selection stage and Stage II being a dose-assessment stage. Four dose groups (placebo and 125, 250 and 500 mg of crofelemer twice daily) will be assessed in Stage I. When 50 subjects per group complete the initial efficacy dosing period (28 days), an interim analysis will be conducted to select an optimal single dose of crofelemer for Stage II. Stage II will continue until an additional 75 subjects are randomized to this dose of crofelemer or placebo, providing for 125 patients on placebo and 125 patients on the selected crofelemer dose. The primary study analysis is planned after all subjects complete the 28-day efficacy period. Subjects who complete the efficacy part of the study will be allowed to continue into a five-month extension.

Crofelemer is extracted from Croton lechleri, a medicinal plant available in several countries in South America. Napo also plans to develop another product, NP-500, for the treatment of insulin-resistant diseases using this plant.