Efficacy and safety of Butantan-DV in participants aged 2-59 years through an extended follow-up: results from a double-blind, randomised, placebo-controlled, phase 3, multicentre trial in Brazil.

BACKGROUND: A single-dose dengue vaccine that protects individuals across a wide age range and regardless of dengue serostatus is an unmet need. We assessed the safety and efficacy of the live, attenuated, tetravalent Butantan-dengue vaccine (Butantan-DV) in adults, adolescents, and children. We previously reported the primary and secondary efficacy and safety endpoints in the initial 2 years of follow-up. Here we report the results through an extended follow-up period, with an average of 3·7 years of follow-up. METHODS: In this double-blind, randomised, placebo-controlled, phase 3, multicentre trial in Brazil, healthy participants (aged 2-59 years) who had not previously received a dengue vaccine were enrolled and randomly assigned 2:1 (stratified by age 18-59 years, 7-17 years, and 2-6 years) using a central electronic randomisation system to receive 0·5 mL of Butantan-DV (containing approximately 103 plaque-forming units of each of the four vaccine virus strains) or placebo, administered subcutaneously. Syringes containing vaccine or placebo were prepared by an unmasked trial pharmacist who was not involved in any subsequent participant assessments; other site staff and the participants remained unaware of the group allocations. Vaccine efficacy was calculated with the accrual of virologically confirmed dengue (VCD) cases (by RT-PCR) at least 28 days after vaccination up until the cutoff (at least 2 years of follow-up from the last participant enrolled). The primary endpoint was vaccine efficacy against VCD after day 28 by any dengue virus (DENV) serotype regardless of dengue serostatus at baseline in the per-protocol population. The primary and secondary safety endpoints up until day 21 were previously reported; secondary safety endpoints include the frequency of unsolicited vaccine-related adverse events after day 22. Safety analyses were done on all participants as treated. This trial is registered with ClinicalTrials.gov (NCT02406729) and is ongoing. FINDINGS: Of 16 363 participants assessed for eligibility, 16 235 were randomly assigned between Feb 22, 2016, and July 5, 2019, and received single-dose Butantan-DV (10 259 participants) or placebo (5976 participants). 16 162 participants (Butantan-DV n=10 215; placebo n=5947) were included in the per-protocol population and 16 235 (Butantan-DV n=10 259; placebo n=5976) in the safety population. At the data cutoff (July 13, 2021), participants had 2-5 years of follow-up (mean 3·7 years [SD 1·0], median 4·0 years [IQR 3·2-4·5]). 356 VCD cases were captured through the follow-up (128 in the vaccine group and 228 in the placebo group). Vaccine efficacy against VCD caused by any DENV serotype was 67·3% (95% CI 59·4-73·9); cases caused by DENV-3 or DENV-4 were not observed. The proportions of participants who had serious adverse events were similar between treatment groups (637 [6·2%] in the vaccine group and 395 [6·6%] in the placebo group) up until the cutoff. INTERPRETATION: A single dose of Butantan-DV was generally well tolerated and efficacious against symptomatic VCD (caused by DENV-1 and DENV-2) for a mean of 3·7 years. These findings support the continued development of Butantan-DV to prevent dengue disease in children, adolescents, and adults regardless of dengue serostatus. FUNDING: Instituto Butantan and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Live, Attenuated, Tetravalent Butantan-Dengue Vaccine in Children and Adults.

BACKGROUND: Butantan-Dengue Vaccine (Butantan-DV) is an investigational, single-dose, live, attenuated, tetravalent vaccine against dengue disease, but data on its overall efficacy are needed. METHODS: In an ongoing phase 3, double-blind trial in Brazil, we randomly assigned participants to receive Butantan-DV or placebo, with stratification according to age (2 to 6 years, 7 to 17 years, and 18 to 59 years); 5 years of follow-up is planned. The objectives of the trial were to evaluate overall vaccine efficacy against symptomatic, virologically confirmed dengue of any serotype occurring more than 28 days after vaccination (the primary efficacy end point), regardless of serostatus at baseline, and to describe safety up to day 21 (the primary safety end point). Here, vaccine efficacy was assessed on the basis of 2 years of follow-up for each participant, and safety as solicited vaccine-related adverse events reported up to day 21 after injection. Key secondary objectives were to assess vaccine efficacy among participants according to dengue serostatus at baseline and according to the dengue viral serotype; efficacy according to age was also assessed. RESULTS: Over a 3-year enrollment period, 16,235 participants received either Butantan-DV (10,259 participants) or placebo (5976 participants). The overall 2-year vaccine efficacy was 79.6% (95% confidence interval [CI], 70.0 to 86.3) - 73.6% (95% CI, 57.6 to 83.7) among participants with no evidence of previous dengue exposure and 89.2% (95% CI, 77.6 to 95.6) among those with a history of exposure. Vaccine efficacy was 80.1% (95% CI, 66.0 to 88.4) among participants 2 to 6 years of age, 77.8% (95% CI, 55.6 to 89.6) among those 7 to 17 years of age, and 90.0% (95% CI, 68.2 to 97.5) among those 18 to 59 years of age. Efficacy against DENV-1 was 89.5% (95% CI, 78.7 to 95.0) and against DENV-2 was 69.6% (95% CI, 50.8 to 81.5). DENV-3 and DENV-4 were not detected during the follow-up period. Solicited systemic vaccine- or placebo-related adverse events within 21 days after injection were more common with Butantan-DV than with placebo (58.3% of participants, vs. 45.6%). CONCLUSIONS: A single dose of Butantan-DV prevented symptomatic DENV-1 and DENV-2, regardless of dengue serostatus at baseline, through 2 years of follow-up. (Funded by Instituto Butantan and others; DEN-03-IB ClinicalTrials.gov number, NCT02406729, and WHO ICTRP number, U1111-1168-8679.).

COL1A1, COL4A3, TIMP2 and TGFB1 polymorphisms in cervical insufficiency.

OBJECTIVES: To investigate the association between selected single nucleotide polymorphisms (SNPs) with cervical insufficiency and its relationship with obstetric history. METHODS: Twenty-eight women with cervical insufficiency (case group) and 29 non-pregnant women (control group) were included. The SNPs sequenced included rs2586490 in collagen type I alpha 1 chain (COL1A1), rs1882435 in collagen type IV alpha 3 chain (COL4A3), rs2277698 in metallopeptidase inhibitor 2 (TIMP2), and rs1800468 in transforming growth factor beta 1 (TGFB1). RESULTS: We found a higher frequency of the normal allele in the control group (65.5%) and the homozygous mutated genotype in the case group (64.3%) for rs2586490 in COL1A1 (p=0.023). An unplanned finding in the cervical insufficiency group was a higher gestational age of delivery (median≥38 weeks) in the mutated allele than in the wild-type genotype (median of 28.2 weeks) for rs2857396, which is also in the COL1A1 gene (p=0.011). CONCLUSIONS: The findings of the present study corroborate the hypothesis that cervical insufficiency has a genetic component and probably involves genes encoding proteins in the extracellular matrix, in addition to inflammatory processes.

Outcomes following medical termination versus prolonged pregnancy in women with severe preeclampsia before 26 weeks.

OBJECTIVE: To compare maternal complications and describe neonatal outcomes in women with severe preeclampsia at ≤ 26+0 weeks in two countries with different management policies: expectant management (Brazil) versus termination of pregnancy (France). METHODS: We conducted a retrospective comparative study by reviewing the medical records of women with severe preeclampsia at ≤ 26+0 weeks, from January 2010 to June 2018, in two centers: Hospital das Clínicas da Faculdade de Medicina, in Sao Paulo, Brazil (where medical abortion is forbidden in this indication) and Hôpital Antoine-Béclère, Clamart, France (where medical termination is accepted). We collected information on maternal characteristics, laboratory tests, maternal complications and fetal and newborn characteristics. We used Student's t-test and the Mann-Whitney U nonparametric test to compare quantitative variables, and Chi-square test or Fisher's exact test to evaluate the associations between the qualitative variables. RESULTS: There was no between-group difference in maternal complications during hospitalization (p = 0.846). In Brazil, the rate of cesarean section was 66.7%, and 20% of patients had vertical incision. The rate of spontaneous fetal death was 35.6% and among the live-born infants 26.6% were discharged from hospital. In France, one patient had a cesarean section with vertical incision. CONCLUSION: When comparing termination of pregnancy to expectant management in severe preeclampsia before 26 weeks, maternal complications were equivalent but maternal reproductive future might have been compromised in 20% of cases due to a higher risk of uterine rupture in subsequent pregnancies for patients having classic cesarean (vertical incision). 26.6% of children survived the neonatal period when pregnancy was pursued, however we lack information on their long-term follow-up.