Tam PYI, Arnold SLM, Barrett LK, et al. - Via performing a randomized, double-blind, placebo-controlled study, researchers investigated efficacy, pharmacokinetics (PK), and safety of clofazimine (CFZ) in HIV-infected patients with cryptosporidiosis. Reduction in Cryptosporidium shedding, safety, and PK were assessed as primary outcomes in Part A. Primary analysis was performed according to protocol (ATP). Comparison of CFZ PK in matched HIV-infected individuals without cryptosporidiosis was done in Part B. The study ATP was completed by 20 Part A and 10 Part B participants. The efficacy of CFZ for the treatment of cryptosporidiosis in a severely immunocompromised HIV population was not supported by this study. This trial, however, suggested a pathway to determine the therapeutic potential of drugs for cryptosporidiosis treatment. Those with failing ARV therapy could be recognized with screening persons with HIV for diarrhea, and especially Cryptosporidium infection. At study entry, higher Cryptosporidium shedding, total stool weight, and more diarrheal episodes were reported in Part A CFZ group vs the placebo group. Over the inpatient period, the CFZ group Cryptosporidium shedding increased by 2.17 log₂ Cryptosporidium per gram stool, total stool weight decreased by 45.3 g, and number of diarrheal episodes increased by 2.32 when compared with those who received placebo.