Immtech International Inc. has completed a special protocol assessment with the FDA for a Phase III study of its anti-infective candidate, DB289, for the treatment of African sleeping sickness.

The randomized, open-label trial is designed to evaluate the efficacy of 100-mg tablets of DB289, administered twice-daily for 10 days vs. the standard treatment of intramuscularly administered pentamidine given once a day for a week.

About 250 patients in the Democratic Republic of the Congo, Sudan and Angola will be examined at the end of the treatment period for clearance of trypanosome parasites from the patients' blood, lymph nodes and cerebrospinal fluid.

While agreement on the SPA does not guarantee product approval, it does ensure that Immtech's pivotal trial addresses objectives that will need to be submitted with a new drug application. Further trial details were not available, though Immtech said the FDA allowed the patient population to include pregnant and nursing women and adolescents 12 years and older.

The company could not be reached for comment. Immtech's stock (AMEX:IMM) gained 6 cents Thursday, to close at $12.97.

The World Health Organization estimates that there are 300,000 to 500,000 active cases in central Africa of African sleeping sickness (trypanosomiasis), a parasitic disease that is spread by tsetse flies and found primarily in the sub-Saharan region.

Immtech's DB289 has been granted fast-track status by the FDA. Results of an 81-patient Phase II study comparing DB289 to pentamidine showed that all the patients receiving Immtech's drug showed no recurrence of the disease at 12 months, while one of the 41 patients treated with pentamidine experienced a relapse. Patients in a Phase IIb study also were found to be clear of the parasite at the end of the 10-day treatment period with DB289, and those who returned for follow-up testing remained clear at three months.

In addition to African sleeping sickness, the Vernon Hills, Ill.-based company also has ongoing clinical trials of DB289 in malaria and pneumocystis pneumonia.