SQUIBB's TIGHTLY-TARGETED MONOBACTAM ANTIBACTERIAL AZACTAM
Executive Summary
SQUIBB's TIGHTLY-TARGETED MONOBACTAM ANTIBACTERIAL AZACTAM is "approvable." FDA notified the company on Oct. 16 that the drug had reached the final stage of agency review. Squibb filed its NDA for Azactam in December 1983. The company initially expected approval of the antibacterial agent during 1985 and has been moving back its projected approval date ever since. The FDA review period for Azactam is now approaching three years. Azactam is designed the agent-of-choice against specific gram-negative infections. During clinical trials, Squibb has touted Azactam's side effect profile v. aminoglycosides. Azactam has shown no risk of hearing loss or kidney damage. At a presentation in 1984, for example, Squibb Exec VP Charles Sanders noted that the company would attempt to "redefine the approach to antibiotic therapy" with its narrow spectrum Azactam. He explained that a narrow spectrum antibiotic like Azactam could have "considerable appeal" because the wide use of broad spectrum antibiotics has contributed to the problem of bacterial resistance. "Thus," Sanders continued, "one could envision the combined use of a complementary broad spectrum antibiotic and Azactam in initial treatment for an infection of an unknown cause and then omitting the broad spectrum antibiotic if the infection is found to be susceptible to Azactam. This approach has the dual advantage of helping to maintain the normal bacterial flora, a necessary feature to preventing invasion of resistant bacteria or fungi, and minimizing the induction of bacterial resistance in bacteria normally found in the environment." In late 1985, Squibb published summaries of its clinical work with Azactam in urinary tract infections and intra-abdominal infections. In 681 patients with gram negaive urinary tract infections, Azactam, given usually with Clindamycin for gram-positive infections, had a cure rate of 85%. In a multi-dose, 625-patient study, Azactam demonstrated a cure rate of 87% v. E. coli, 90% v. Klebsiella-Enterobacter-Serratia strains, and 86% v. P. aeruginosa, Squibb reported. The intra-abdominal studies showed Azactam with a cure rate of 90% in 113 patients, including 11 of 13 patients with P. aeruginosa, all of which responded. In one in vitro study in the scientific literature, Azactam demonstrated 99-100% efficacy v. strains of E. coli and Enterobacter species, Klebsiella, Proteus mirabilis and P. vulgaris, Providencia rettgeri and P. stuartii, and Serratia marcescans. The drug also showed in vitro activity against 90% of the P. aeruginosa strains. Azactam will be Squibb's first new anti-infective product launch since Velosef (cephradine) over 10 years ago. Although a relatively mature cephalosporin product, Velosef sales continue to grow -- Squibb reported that third quarter sales of the antibiotic were up 15% over the same period in 1985. Following Azactam, Squibb's monobactam research program has two other anti-infectives in its clinical program. Tigemonam, an oral monobactam, is in Phase II clinicals. A second generation synthetic monobactam injectable antibiotic, SQ-83360, is expected to enter clinicals in late 1986/early 1987.