ZYC101a for Treatment of High-Grade Cervical Intraepithelial Neoplasia: A Randomized Controlled Trial

OBJECTIVE:The objective of this study was to assess the safety and efficacy of a novel therapeutic, ZYC101a, for the treatment of women with histologically confirmed cervical intraepithelial neoplasia (CIN) 2/3. ZYC101a contains plasmid-DNA–encoding fragments derived from the E6 and E7 proteins of human papillomavirus (HPV) 16 and 18, and is formulated within small biodegradable microparticles. METHODS:A multicenter, double-blind, randomized, placebo-controlled trial was conducted in a group of women with biopsy-confirmed CIN 2/3. Subjects were randomized to 3 intramuscular doses of either placebo or ZYC101a (100 or 200 μg). Six months after the first injection, subjects underwent cervical conization. The primary endpoint for this study was histologically confirmed resolution of CIN 2/3. A total of 161 subjects were randomized, dosed, and evaluated for safety. After central pathology review, 127 subjects were evaluable for efficacy. RESULTS:The most common adverse events were related to the injection site, were mild to moderate, and did not worsen at later treatments. The proportion of subjects who resolved was higher in the ZYC101a groups compared to placebo (43% versus 27%), but the difference was not statistically significant (P = .12). In a prospectively defined population of women younger than 25 years (n = 43), resolution was significantly higher in the combined ZYC101a groups compared to placebo (70% versus 23%; P = .007). ZYC101a activity was not restricted to HPV-16– or HPV-18–positive lesions. CONCLUSIONS:ZYC101a was shown to be well tolerated in all patients and to promote the resolution of CIN 2/3 in women younger than 25 years. LEVEL OF EVIDENCE:I