At this week's Interscience Conference on Antimicrobial Agents and Chemotherapy in Chicago, Stressgen Biotechnologies Corp. said a Phase II study of HspE7 hit its primary endpoint in treating recurrent respiratory papillomatosis (RRP).

The interim findings revealed that treatment with the product resulted in a longer period between surgeries compared with a pretreatment surgical interval. More specifically, the data showed a statistically significant increase in the first post-treatment intersurgical interval (p<0.01) and a statistically significant increase in the median of all post-treatment intervals (p<0.05).

Other data indicated that the annual number of surgeries RRP patients would require was reduced by 37 percent with HspE7 therapy, another statistically significant reduction (p<0.0001).

For the overall population suffering with the debilitating and sometimes life-threatening condition for children, the first post-treatment interval increased 78.6 percent over the pretreatment interval, resulting in fewer surgeries for patients. Almost half the children were rated severe by a laryngeal scale score or by having papillomas in their lungs - the most serious manifestation of RRP.

The Victoria, British Columbia-based company said more than 50 surgeries will be avoided during the year after HspE7 treatment among patients who experienced at least one surgery reduction compared with the pretreatment period. Stressgen noted that additional Phase II results, including follow-up data on about 50 percent of the patients who have completed the 60-week study, will be presented at the Society for Ear, Nose and Throat Advances in Children meeting that begins late next month in New Orleans.

In other news from the conference:

• Avant Immunotherapeutics Inc., of Needham, Mass., said full results from an evaluation of its oral cholera vaccine candidate, CholeraGarde, pointed to a dose-response relationship and showed the vaccine's ability to elicit vibriocidal antibodies without an increased incidence of adverse effects compared to placebo in healthy volunteers who took part in the study. Phase II field trials of CholeraGarde in adults and children are being conducted by the International Vaccine Institute in Bangladesh.

• Cubist Pharmaceuticals Inc., of Lexington, Mass., said more than 30 Cubist-related posters were scheduled for presentation during the conference by internal researchers and external investigators. Among them, one highlighted findings from two Phase III studies of daptomycin (Cubicin), which received FDA approval days before the conference began. The multicenter, multinational, investigator-blinded, randomized studies compared injectable daptomycin with semi-synthetic penicillin or vancomycin for seven to 14 days of treatment for complicated skin and skin-structure infections (cSSSIs) in adults. Data showed that the clinical success rates of daptomycin were statistically equivalent to the vancomycin subgroup in treating MRSA (methicillin-resistant Staphylococcus aureus) or the penicillin arm in treating MSSA (methicillin-susceptible S. aureus). Cubicin, previously named Cidecin, was approved for cSSSI caused by Gram-positive bacteria. (See BioWorld Today, Sept. 16, 2003.)

• Enanta Pharmaceuticals Inc., of Watertown, Mass., said a series of 12 posters revealed new data from its macrolide antibiotic program, including findings on new classes of the antibacterial agents it discovered and is developing for community-acquired respiratory tract infections, as well as hospital-acquired infections. Also, Enanta reported data on several promising preclinical lead compounds undergoing in vitro and in vivo evaluations for community-acquired respiratory tract infections, as well as another lead compound that demonstrated activity against resistant hospital pathogens, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.

• Genelabs Technologies Inc., of Redwood City, Calif., reported in vivo efficacy studies on its preclinical antifungal candidate, GL48656. In a mouse model of systemic aspergillosis, Genelabs reduced the frequency of dosing with the compound to once per day, and treated the subject animals with 1.0, 3.3 or 10 mg/kg of GL48656. All three doses resulted in 100 percent survival (p=0.011), equivalent to optimized doses of 1.0 and 3.3 mg/kg amphotericin B in prolonging survival. Among untreated controls, the death rate was 50 percent. Also, aspergillus colony-forming units in the brains and kidneys, target organs for the infection, were significantly reduced by all GL48656 treatment regimens, equivalent to the optimized doses of amphotericin B for each organ. Treatment with GL48656 at 3.3 mg/kg was superior to both doses of amphotericin B in reducing aspergillus colony-forming units in the kidneys, it said.

• InterMune Inc., of Brisbane, Calif., reported positive results from a second Phase III trial of oritavancin, its investigational intravenous antibiotic for complicated skin/skin-structure infections caused by Gram-positive bacteria, as well as nine additional abstracts concerning the drug's distribution, resistance profile and bactericidal properties. Data showed oritavancin achieved its primary efficacy endpoint, demonstrating that the drug was as effective as the comparator regimen of vancomycin followed by cephalexin, over a period of administration of 5.3 days compared to 10.9 days for the comparator group. The 1,267-patient study also revealed a significantly better safety profile with 11.1 percent fewer patients in the oritavancin group experiencing an adverse event compared with patients treated with vancomycin/cephalexin (p<0.001). InterMune first reported top-line data from the study three months ago. (See BioWorld Today, June 13, 2003.)

• Vertex Pharmaceuticals Inc., of Cambridge, Mass., and GlaxoSmithKline plc, of London, reported clinical data from two studies of their investigational HIV protease inhibitor 433908 showing that the compound can be co-administered with the antacids Maalox TC or Zantac as well as the cholesterol-lowering Lipitor (atorvastatin). When dosed in combination with 908, Maalox TC and Zantac decreased plasma APV AUC by 18 percent and 30 percent, respectively. Plasma C12 concentrations of APV were unaffected by Maalox or Zantac. Separately, researchers found that plasma concentrations of Lipitor were significantly increased when co-administered with 908 or 908/ritonavir, but Lipitor had no significant effect on the pharmacokinetics of APV.