If Shaman Pharmaceuticals Inc.'s diarrhea drug, Provir, proves assuccessful as suggested by a recently completed Phase II open-labeltrial, the company's product may take the fear out of drinking thelocal water for travelers worldwide.
Results of the clinical study involving 75 patients with secretory, orwatery, diarrhea, showed 89 percent experienced normal bowelfunction within two days of treatment and more than 50 percent ofthose had recovered in one day. In addition, during a 72-hour follow-up period, no recurrences were seen.
Lisa Conte, president and CEO of South San Francisco-basedShaman, said the first 25 patients treated were afflicted withtravelers' diarrhea, which is caused most commonly by Escherichiacoli. The other 50 people contracted watery diarrhea from unknownorigin and the effectiveness of Provir in that category, she noted,could lead to wider use of the drug.
More than 16 million people spend an estimated $1.2 billion a yearon antibiotics or anti-motility drugs, which reduce gastrointestinalactivity, to treat watery diarrhea.
The disorder is caused by over secretion of chloride ions, triggeredby an infectious agent, in the epithelial cells of the intestine resultingin a build-up of water, followed by diarrhea and eventualdehydration.
If left untreated the condition lasts up to seven days. The currenttherapies, Conte noted, usually take three to five days to work andrecurrence of the diarrhea is not uncommon.
Provir, an oral drug, is derived from an extract of the croton plantfound in Latin America. Rather than attacking the infectious microbeor inhibiting gastrointestinal activity, the drug targets the underlyingcellular mechanism for the diarrhea by blocking chloride secretion. Inmost cases, a patient's own immune response can dispatch the bugs.
Conte also said Provir, which has proved safe, is not absorbed intothe patients' systems, greatly limiting the potential for any adverseevents.
Antibiotics and anti-motility drugs can have undesired side effects.For example, concern for bacterial resistance to over-prescribedantibiotics has increased pressure to limit their use. Anti-motilitydrugs can cause constipation and are potentially dangerous forchildren.
In January 1997, Shaman will begin a two-month, 400-patient,placebo-controlled trial of Provir to determine the minimal doseneeded and frequency. Two simultaneous Phase III studies willfollow in May and results are expected in the fall.
If the pivotal trials are successful, the company expects to submit anew drug application to the FDA in the first half of 1998.
Shaman's stock (NASDAQ:SHMN) closed Thursday at $6.625, up$0.875.
The company uses an ethnobotanical approach to drug discovery,screening extracts of medicinal plants for their active ingredients.Traditional uses of the croton plant include treatments for respiratorydiseases and gastrointestinal disorders.
In addition to Provir, Shaman has a topical version of the drug, calledVirend, in clinical development for herpes. n
-- Charles Craig
(c) 1997 American Health Consultants. All rights reserved.