[Show abstract][Hide abstract] ABSTRACT: Therapy for chronic hepatitis C (CHC) has limited efficacy, adverse effects, and high costs. Cohort and vaccine-based preclinical studies have indicated the importance of T-cell-based immunity in controlling viral infection. TG4040 is a recombinant poxvirus vaccine that expresses the hepatitis C virus (HCV) proteins NS3, NS4, and NS5B. We performed a phase I clinical trial to assess the safety, immunogenicity, and early antiviral efficacy of TG4040 in patients with CHC.
In an open-label, dose-escalating study, patients with mild CHC (genotype 1) were assigned to 3 groups of 3 patients each; they received subcutaneous injections of 10⁶, 10⁷, or 10⁸ plaque-forming units of TG4040 on study days 1, 8, and 15. Six additional patients were given the highest dose of vaccine (10⁸ plaque-forming units). Patients were followed for 6 months after the last injection. T-cell-based and antibody responses and levels of HCV RNA were measured.
All 3 doses of TG4040 were well tolerated, without serious adverse events. Vaccine-induced HCV-specific cellular immune responses were observed in 5 of the 15 patients (33%). A transient decrease in circulating levels of HCV RNA, from -0.52 log₁₀ to -1.24 log₁₀, was observed in 8 patients; in 5 patients, the lowest level of HCV RNA was observed on day 37, after the first injection. The most pronounced decrease in viral load occurred in 2 patients, who also had marked vaccine-induced T-cell responses.
In patients with CHC, the viral-vector-based vaccine TG4040 had a good safety profile, induced HCV-specific cellular immune responses, and reduced viral load. This vaccine should be investigated in further clinical studies, in combination with standard of care.
No preview · Article · Jun 2011 · Gastroenterology
[Show abstract][Hide abstract] ABSTRACT: We sought to evaluate the safety and efficacy of TG4001 in patients with human papillomavirus (HPV) 16-related cervical intraepithelial neoplasia (CIN) 2/3 at 6 and 12 months.
In all, 21 patients with HPV 16-related CIN 2/3 received 3 weekly subcutaneous injections of TG4001. Regression of the CIN 2/3 lesion and the clearance of HPV 16 infection were monitored by cytology, colposcopy, and HPV DNA/messenger RNA (mRNA) detection. A clinical response was defined by no CIN 2/3 found on conization, or no conization performed because not suspected at cytology or colposcopy.
Ten patients (48%) were evaluated as clinical responders at month 6. Nine patients experienced an improvement of their HPV 16 infection, by mRNA ± DNA eradication. HPV 16 mRNA clearance was associated with CIN 2/3 cytologic and colposcopic regression in 7 of 10 patients. At month 12, 7 of 8 patients without conization reported neither suspicion of CIN 2/3 relapse nor HPV 16 infection. The remaining patient was lost to follow-up.
These promising data warrant further development of TG4001 in CIN 2/3 treatment.
No preview · Article · Feb 2011 · American journal of obstetrics and gynecology