Development of an mRNA-based therapeutic vaccine mHTV-03E2 for high-risk HPV-related malignancies.

Human papillomavirus (HPV) 16 and 18 infections are related to many human cancers. Despite several preventive vaccines for high-risk (hr) HPVs, there is still an urgent need to develop therapeutic HPV vaccines for targeting pre-existing hrHPV infections and lesions. In this study, we developed a lipid nanoparticle (LNP)-formulated mRNA-based HPV therapeutic vaccine (mHTV)-03E2, simultaneously targeting the E2/E6/E7 of both HPV16 and HPV18. mHTV-03E2 dramatically induced antigen-specific cellular immune responses, leading to significant CD8+ T cell infiltration and cytotoxicity in TC-1 tumors derived from primary lung epithelial cells of C57BL/6 mice expressing HPV E6/E7 antigens, mediated significant tumor regression, and prolonged animal survival, in a dose-dependent manner. We further demonstrated significant T cell immunity against HPV16/18 E6/E7 antigens for up to 4 months post-vaccination in immunological and distant tumor rechallenging experiments, suggesting robust memory T cell immunity against relapse. Finally, mHTV-03E2 synergized with immune checkpoint blockade to inhibit tumor growth and extend animal survival, indicating the potential in combination therapy. We conclude that mHTV-03E2 is an excellent candidate therapeutic mRNA vaccine for treating malignancies caused by HPV16 or HPV18 infections.

Sustained serological and complete responses in HBeAg-positive patients treated with Peginterferon alfa-2b: a 6-year long-term follow-up of a multicenter, randomized, controlled trial in China.

BACKGROUND: Pegylated interferon (PEG-IFN) alfa-2b is recommended for chronic hepatitis B (CHB). We aimed to investigate the sustainability of off-treatment responses among Chinese HBeAg-positive CHB patients treated with PEG-IFN alfa-2b from a randomized trial. METHODS: Eligible Chinese patients (n = 322) were followed up by one visit after a median of 6 years (LTFU) following their participation in a randomized trial evaluating the efficacy of three PEG-IFN alfa-2b dosing regimens (1.0 or 1.5 µg/kg/wk. 24 weeks or 1.5 µg/kg/wk. 48 weeks). Primary endpoints at the LTFU were sustained SR and CR (SR/CR at the end of original study [EOS] and at the LTFU). SR was defined as HBeAg loss and seroconversion to anti-HBe and CR as HBeAg loss and seroconversion to anti-HBe and HBV-DNA < 2000 IU/mL. RESULTS: The proportions of patients achieving sustained SR among patients who had SR at EOS were high in three treatment groups (61.9, 65.5, 76.5%, respectively, p = 0.46); treatment with PEG-IFN alfa-2b 1.5 µg/kg/wk. 48 weeks had the highest proportion of a sustained CR among patients who had CR at EOS (75.0%, p = 0.05). A considerable number of patients achieved sustained SR (18.2-29.9%) and sustained CR (14.8-18.3%) after EOS despite no further NA treatment. At the LTFU, rates of SR and CR were less than 70.0 and 50.0%, respectively, among all enrolled patients regardless of additional nucleos(t)ide analogs before the LTFU. CONCLUSIONS: PEG IFN alfa-2b therapy had considerable off-treatment sustainability in Chinese HBeAg positive chronic hepatitis B patients with serological and complete responses.

HBsAg and HBeAg in the prediction of a clinical response to peginterferon α-2b therapy in Chinese HBeAg-positive patients.

BACKGROUND: This study aimed to evaluate the predictive values of hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) levels in 171 Chinese patients with chronic hepatitis B who received a 48-week course of pegylated interferon alfa-2b therapy at 1.5 mcg/kg. METHODS: HBsAg, HBeAg, and hepatitis B virus (HBV) DNA levels were measured at baseline and weeks 12, 24, 48, and 72. Clinical responses were defined as a combined response (CR, HBeAg seroconversion [sustained response, SR] combined with HBV DNA level <2,000 IU/mL at week 72). The positive predictive value and negative predictive value were calculated for HBsAg alone and/or combined with HBeAg and HBV DNA at weeks 12 and 24. RESULTS: Of 171 patients included, 58 (33.9 %) achieved a SR. Of patients who achieved a SR, 33 (56.9 %) achieved a CR. Totally 19.3 % (33/171) patients achieved CR and 80.7 % (138/171) patients did not. Patients with HBsAg <1500 IU/mL at week 12 had a 47.4 % chance of achieving an off-treatment SR and patients with a HBsAg decrease >1.5 logIU/mL at week 12 had a 54.5 % chance. Patients with HBsAg >20,000 IU/mL at weeks 12 and 24 had a 93.8 and 100.0 % chance, respectively, of not achieving a CR. An HBsAg level or changes at weeks 12 and 24, combined with HBeAg or HBV DNA, increased the chance for a SR and CR. CONCLUSIONS: On-treatment HBsAg quantification, alone or in combination with HBeAg or HBV DNA, predicted off-treatment SR and CR after 48 weeks of PEG-IFNα-2b therapy, and thus, may guide clinicians in making a therapeutic decision to continue or terminate the therapy.