Generation and efficacy assessment of a chimeric antigen E2-CD154 as a marker Classical Swine Fever Virus subunit vaccine produced in HEK 293 and CHO K1 mammalian cells

The E2 glycoprotein is the major antigen that induces neutralizing and protective antibodies in CSFV infected pigs, thus a marker vaccine based on this antigen appears to be the most promising alternative to induce a protective immune response against CSFV. However, the structural characteristics of this protein state the necessity to produce glycoprotein E2 in more complex expression systems such as mammalian cells. In this study, we use a lentivirus-based gene delivery system to establish a stable recombinant HEK 293 and CHO K1 cell line for the expression of E2 fused to porcine CD154 as immunostimulatory molecule. In a first experiment, E2his and E2-CD154 were compared in an immunization trial. The average antibody titers in E2his immunized pigs was in the range of 30-40% of blocking and the average antibody titers for E2-CD154 are above 40% at day 14, meaning that the chimeric antigen is able to raise antibodies at positive levels in a shorter time. Additionally, the blocking rate of E2his vaccinated group in ELISA ranged between 66-88% and in the E2-CD154- vaccinated groups ranged between 86-92%, one week after booster immunization. The NPLA antibody titers also increased greatly. Later on, the protective capacity of purified E2-CD154 glycoprotein was demonstrated in a challenge experiment in pigs using a biphasic immunization schedule with 25 and 50 μg. The immunized animals developed neutralizing antibodies that were protective when the animals were faced to a challenge with 105 LD50 of ‘‘Margarita’’ CSFV highly pathogenic strain. No clinical signs of the disease were detected in the vaccinated pigs. Unvaccinated pigs in the control group exhibited symptoms of CSF at 3–4 days after challenge and were euthanized from 7–9 days when the pigs became moribund. These results indicate that E2-CD154 produced in recombinant HEK 293 and CHOK1cell line is a high quality candidate for the development of a safe and effective CSFV subunit vaccine. In the next steps, pilot and production scale, E2-CD154 expression levels should be increased in 10 to 50 fold, arriving to a very attractive productive platform for an implementation of a commercial subunit vaccine against CSF

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer

Background: The randomized, double-blind OlympiA trial compared 1 year of the oral poly(adenosine diphosphate-ribose) polymerase inhibitor, olaparib, to matching placebo as adjuvant therapy for patients with pathogenic or likely pathogenic variants in germline BRCA1 or BRCA2 (gBRCA1/2pv) and high-risk, human epidermal growth factor receptor 2-negative, early breast cancer (EBC). The first pre-specified interim analysis (IA) previously demonstrated statistically significant improvement in invasive disease-free survival (IDFS) and distant disease-free survival (DDFS). The olaparib group had fewer deaths than the placebo group, but the difference did not reach statistical significance for overall survival (OS). We now report the pre-specified second IA of OS with updates of IDFS, DDFS, and safety. Patients and methods: One thousand eight hundred and thirty-six patients were randomly assigned to olaparib or placebo following (neo)adjuvant chemotherapy, surgery, and radiation therapy if indicated. Endocrine therapy was given concurrently with study medication for hormone receptor-positive cancers. Statistical significance for OS at this IA required P < 0.015. Results: With a median follow-up of 3.5 years, the second IA of OS demonstrated significant improvement in the olaparib group relative to the placebo group [hazard ratio 0.68; 98.5% confidence interval (CI) 0.47-0.97; P = 0.009]. Four-year OS was 89.8% in the olaparib group and 86.4% in the placebo group (Δ 3.4%, 95% CI -0.1% to 6.8%). Four-year IDFS for the olaparib group versus placebo group was 82.7% versus 75.4% (Δ 7.3%, 95% CI 3.0% to 11.5%) and 4-year DDFS was 86.5% versus 79.1% (Δ 7.4%, 95% CI 3.6% to 11.3%), respectively. Subset analyses for OS, IDFS, and DDFS demonstrated benefit across major subgroups. No new safety signals were identified including no new cases of acute myeloid leukemia or myelodysplastic syndrome. Conclusion: With 3.5 years of median follow-up, OlympiA demonstrates statistically significant improvement in OS with adjuvant olaparib compared with placebo for gBRCA1/2pv-associated EBC and maintained improvements in the previously reported, statistically significant endpoints of IDFS and DDFS with no new safety signals

Overall survival in the OlympiA phase III trial of adjuvant olaparib in patients with germline pathogenic variants in BRCA1/2 and high-risk, early breast cancer

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