By Mary Welch
StressGen Biotechnologies Corp. will move the HspE7 fusion protein, straight into Phase III trials after a successful interim analysis of a Phase II trial for anal dysplasia .
"It's fantastic news," said Elisabeth Whiting, StressGen's director of corporate communications. "There were a couple of different ways the analysis could have gone, and we ended up with a very positive result. We saw a high level of activity in the open-label study and some results we didn't expect to see."
The Phase II trial, which involved two sites in the U.S., will stop patient enrollment. So far, only 85 out of a planned 180 patients were enrolled. Those who were treated will continue with the program.
StressGen does not have the statistical information concerning the trial, but will present the data at the International Human Papillomavirus conference in Barcelona, Spain, next month.
Anal dysplasia is characterized by the presence of abnormal cells that may precede the development of anal cancer.
The Victoria, British Columbia-based company anticipates moving quickly into a Phase III trial. "We are hoping to start enrollment by the end of the year or early [in the first quarter next year]," she said. "It will be a trial involving 100 to 150 patients in three to six sites in the United States. We were able to enroll patients pretty quickly for the Phase II trial, and we expect that it will be the same for the Phase III."
The endpoint will be similar to that of the Phase II trial, which was disease regression. The company plans a second Phase III trial starting early next year that will confirm the Phase II data and dose regulation.
The Phase II study also produced data that prompted StressGen to expand HspE7's range to include genital warts. Genital warts are caused by the human papillomavirus, one of the most prevalent sexually transmitted diseases.
"We don't know whether we'll start a separate trial for the genital warts indication," Whiting said. "We may be able to include it in the Phase III trials alongside AIN."
The company currently is conducting a Phase II trial for women with high-grade cervical dysplasia, a condition characterized by the presence of abnormal cells that often precede cervical cancer. It also is planning to start a Phase II trial for cervical cancer.
HspE7 is a recombinant candidate that consists of the heat shock protein 65 from the genome Mycobacteria fused to an immunogenic oncogene, E7, on Papilloma virus type 16, which perpetrates cervical and anal cancer. Heat shock proteins, also called stress proteins, are known to elicit a powerful immune response. The E7 protein, a tumor-specific antigen involved in the malignant transformation of anal and cervical epithelial cells, represents a precise target for the immune system attack.
StressGen's stock (TSE:SSB) closed Tuesday at C$7.35 (US$4.95), up C$1.10 (US 74 cents).