PFIZER’s STREPTOMYCIN SUPPLEMENTAL NDA FOR MULTI-DRUG RESISTANT TB
Executive Summary
PFIZER's STREPTOMYCIN SUPPLEMENTAL NDA FOR MULTI-DRUG RESISTANT TB filed on Oct. 13., the firm announced Oct. 14 at the Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) held in Anaheim. Pfizer began supplying streptomycin to the Centers for Disease Control for distribution to patients with multi-drug resistant tuberculosis during the summer. Pfizer said it donated approximately 7,000 one gram vials of the drug to CDC in July and another shipment of "more than 30,000" vials in September. Each vial represents the normal daily dosage for most patients. However, CDC said that weekly dosage regimens can vary among patients receiving the drug. Pfizer and Lilly stopped manufacturing streptomycin in May 1991 ("The Pink Sheet" April 6, T&G-11), which contributed to a national shortage of the drug for TB patients ("The Pink Sheet" Jan. 27, T&G-10). Glaxo of Canada supplied streptomycin free of charge to CDC from mid-April until Pfizer was able to begin manufacturing the drug in July. CDC says it no longer has a supply shortage. Pfizer has offered to donate additional shipments of the drug if CDC is faced with another shortage. ICN Canada has continued supplying CDC with Nemasol (para- amino salicylate sodium), which also is used to treat TB. Both ICN Canada and Glaxo of Canada received IND exemptions sponsored by CDC in order to supply the respective TB drugs. Warner-Lambert's quinolone antibiotic drug candidate, sparfloxacin, is under study as a possible tuberculosis therapy. In an ICAAC poster session French researchers C. Truffot-Pernot et al. reported that sparfloxacin, when administered to TB-infected mice, has greater activity versus TB bacteria than either ofloxacin or isoniazide and comparable activity to rifampin. In other mice studies, the researchers said sparfloxacin showed "very promising bactericidal activities." They concluded that sparfloxacin "is the first lead to an important anti-tuberculosis drug in many years, and may play an important role for the treatment of multiple drug resistant tuberculosis." Warner-Lambert said it is not pursuing approval of sparfloxacin for TB, but that it has been in discussions with "several government agencies" about the possibility of a federally sponsored trial for that indication. The drug, licensed from Dainippon and under a comarketing agreement for North America with Rhone-Poulenc Rorer, is in Phase III study as a broad-spectrum antibiotic and in early clinical study for the treatment of Mycobacterium avium complex in AIDS patients.