Dipexium Pharmaceuticals said today it will review pursuing other indications for its diabetic foot ulcer candidate Locilex® (pexiganan cream 0.8%) after topline results showed that Locilex failed two Phase III trials.
Dipexium acknowledged that Locilex did not meet the primary clinical endpoint of superiority versus placebo or “vehicle”—namely the cream without its active ingredient of pexiganan—plus standardized wound care in the OneStep-1 and OneStep-2 clinical trials, which assessed the candidate in patients with mild infections of diabetic foot ulcers (mild DFI).
Locilex also did not show any meaningful difference in wound closure rate compared with vehicle, and neither trial met secondary endpoints of demonstrating a higher rate of eradication of bacteria for the Locilex arm, Dipexium added.
“Although we are disappointed with these results, we are continuing to evaluate the data and will consider potential regulatory pathways forward in other possible clinical indications based on an evaluation of all data emerging from the Phase III studies,” Dipexium President and CEO David P. Luci said in a statement.
The Phase III failures sent shares of Dipexium plunging 83% from yesterday’s close of $12.75, to $2.15 as of 10:15 a.m.
OneStep-1 and OneStep-2 enrolled a total of 389 patients at 59 separate centers in the U.S. Patients were randomized 1:1 to receive either topical Locilex® plus standard local wound care or placebo cream plus standard local wound care for 14 days, with final evaluation at day 28.
Robert J. DeLuccia, Dipexium’s executive chairman, added that the trials were the first ever placebo-controlled studies conducted for mildly infected diabetic foot ulcers: “Since antibiotics are generally used by clinicians to treat an infected ulcer, no clinical trial in diabetic foot infection has ever established a 'response rate' for an ulcer infection that had standardized wound care but was untreated with an antibiotic.”
Serious adverse events with Locilex included higher than anticipated osteomyelitis and cellulitis in the Locilex arm of each study, the company reported, though the overall adverse event incidence was comparable to vehicle alone.
“The results of this study will provide important information regardless of the outcome,” added Benjamin A. Lipsky, M.D., chair of the OneStep trials. “This will include a better understanding of the natural course of diabetic foot ulcer and infection, and a recognition that some mild DFI patients may not need antibacterial treatment.”
Locilex is a chemically synthesized, 22-amino-acid peptide isolated from the skin of the African clawed frog. Unlike most antibiotics, which inhibit bacterial replication, Locilex is designed to kill microbial targets through disruption of bacterial cell membrane permeability in a broad spectrum of Gram-positive, Gram-negative, aerobic, and anerobic bacteria, as well as fungi.