A Phase 4, multicentre, randomized, single-blind clinical trial to evaluate the immunogenicity of the live, attenuated, oral rotavirus vaccine (116E), ROTAVAC®, administered simultaneously with or without the buffering agent in healthy infants in India

Phase III randomized clinical studies to evaluate the immunogenicity, lot-to-lot consistency, and safety of ROTAVAC® liquid formulations (ROTAVAC 5C & 5D) and non-inferiority comparisons with licensed ROTAVAC® (frozen formulation) in healthy infants

The WHO pre-qualified rotavirus vaccine, ROTAVAC®, is derived naturally from the neonatal 116E rotavirus strain, and stored at -20°C. As refrigerator storage is preferable, immunogenicity and safety of liquid formulations kept at 2-8°C, having excipients to stabilize the rotavirus, with or without buffers, were compared with ROTAVAC® in different clinical studies. Study-1, the pivotal trial for this entire product development work, was a randomized, single-blind trial with two operationally seamless phases: (i) an exploratory phase involving 675 infants in which two formulations, ROTAVAC 5C (LnHRV-1.5 mL and LnHRV-2.0 mL) containing buffer and excipients to stabilize the virus against gastric acidity and temperature, were compared with ROTAVAC®. As the immune response of ROTAVAC 5C (LnHRV-2.0 mL) was non-inferior to ROTAVAC®, it was selected for (ii) confirmatory phase, involving 1,302 infants randomized 1:1:1:1 to receive three lots of LnHRV-2.0 mL, or ROTAVAC®. Primary objectives were the evaluation of non-inferiority and lot-to-lot consistency. The secondary objectives were to assess the safety and interference with the concomitant pentavalent vaccine. As it was separately established that buffers are not required for ROTAVAC®, in Study-2, the safety and immunogenicity of ROTAVAC 5D® (with excipients) were compared with ROTAVAC® and lot-to-lot consistency was assessed in another study. All lots elicited consistent immune responses, did not interfere with UIP vaccines, and had reactogenicity similar to ROTAVAC®. ROTAVAC 5C and ROTAVAC 5D® were immunogenic and well tolerated as ROTAVAC®. ROTAVAC 5D® had comparable immunogenicity and safety profiles with ROTAVAC® and can be stored at 2-8°C, leading to WHO pre-qualification.Clinical Trials Registration: Clinical Trials Registry of India (CTRI): CTRI/2015/02/005577CTRI/2016/11/007481 and CTRI/2019/03/017934.

Safety and immunogenicity of human neonatal RV3 rotavirus vaccine (Bio Farma) in adults, children, and neonates in Indonesia: Phase I Trial

BACKGROUND

Despite safe and effective WHO prequalified rotavirus vaccines, at least 84 million children remain unvaccinated. A birth dose schedule of the RV3-BB vaccine was reported to be highly efficacious against severe rotavirus disease in Indonesian infants and is under further development at PT Bio Farma, Indonesia. The aim is to develop a rotavirus vaccine starting from birth that could improve the implementation, safety, and effectiveness of vaccines.

METHODS

A multi-site phase I study of a human neonatal RV3 rotavirus vaccine (Bio Farma) in adults, children, neonates in Indonesia from April 2018 to March 2019. The adult and child cohorts were open-labeled single-dose, while the neonatal cohort was randomized, double-blind, and placebo-controlled three-doses at the age of 0-5 days, 8-10 weeks, and 12-14 weeks. The primary objective was to assess the safety of vaccines with the immunogenicity and vaccine virus fecal shedding as the secondary endpoints in neonates.

RESULTS

Twenty-five adults, 25 children, and 50 neonates were recruited, and all but one in the neonatal cohort completed all study procedures. Three serious adverse events were reported (1 adult & 2 neonates), but none were assessed related to investigational product (IP). The neonatal vaccine group had a significantly higher positive immune response (cumulative seroconverted SNA and IgA) 28 days after three doses than those in the placebo group (72% vs. 16.7%, respectively). The GMT of serum IgA in the vaccine group was significantly higher at post IP dose 1 (p < 0.05) and post IP dose 3 (p < 0.001) compared to the placebo group.

CONCLUSION

The trial results show that the RV3 rotavirus vaccine (Bio Farma) is well tolerated in all participant cohorts (adults, children, and neonates). Three doses of this vaccine administered in a neonatal schedule were immunogenic. These promising results support further clinical development of the RV3 rotavirus vaccine (Bio Farma).

Immunogenicity and safety of two monovalent rotavirus vaccines, ROTAVAC® and ROTAVAC 5D® in Zambian infants

BACKGROUND AND AIMS

ROTAVAC® (frozen formulation stored at -20 °C) and ROTAVAC 5D® (liquid formulation stable at 2-8 °C) are rotavirus vaccines derived from the 116E human neonatal rotavirus strain, developed and licensed in India. This study evaluated and compared the safety and immunogenicity of these vaccines in an infant population in Zambia.

METHODS

We conducted a phase 2b, open-label, randomized, controlled trial wherein 450 infants 6 to 8 weeks of age were randomized equally to receive three doses of ROTAVAC or ROTAVAC 5D, or two doses of ROTARIX®. Study vaccines were administered concomitantly with routine immunizations. Blood samples were collected pre-vaccination and 28 days after the last dose. Serum anti-rotavirus IgA antibodies were measured by ELISA, with WC3 and 89-12 rotavirus strains as viral lysates in the assays. The primary analysis was to assess non-inferiority of ROTAVAC 5D to ROTAVAC in terms of the geometric mean concentration (GMC) of serum IgA (WC3) antibodies. Seroresponse and seropositivity were also determined. Safety was evaluated as occurrence of immediate, solicited, unsolicited, and serious adverse events after each dose.

RESULTS

The study evaluated 388 infants in the per-protocol population. All three vaccines were well tolerated and immunogenic. The post-vaccination GMCs were 14.0 U/mL (95% CI: 10.4, 18.8) and 18.1 U/mL (95% CI: 13.7, 24.0) for the ROTAVAC and ROTAVAC 5D groups, respectively, yielding a ratio of 1.3 (95% CI: 0.9, 1.9), thus meeting the pre-set non-inferiority criteria. Solicited and unsolicited adverse events were similar across all study arms. No death or intussusception case was reported during study period.

CONCLUSIONS

Among Zambian infants, both ROTAVAC and ROTAVAC 5D were well tolerated and the immunogenicity of ROTAVAC 5D was non-inferior to that of ROTAVAC. These results are consistent with those observed in licensure trials in India and support use of these vaccines across wider geographical areas.

Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine, BBV152: a double-blind, randomised, phase 1 trial

BACKGROUND

To mitigate the effects of COVID-19, a vaccine is urgently needed. BBV152 is a whole-virion inactivated SARS-CoV-2 vaccine formulated with a toll-like receptor 7/8 agonist molecule adsorbed to alum (Algel-IMDG) or alum (Algel).

METHODS

We did a double-blind, multicentre, randomised, controlled phase 1 trial to assess the safety and immunogenicity of BBV152 at 11 hospitals across India. Healthy adults aged 18-55 years who were deemed healthy by the investigator were eligible. Individuals with positive SARS-CoV-2 nucleic acid and/or serology tests were excluded. Participants were randomly assigned to receive either one of three vaccine formulations (3 μg with Algel-IMDG, 6 μg with Algel-IMDG, or 6 μg with Algel) or an Algel only control vaccine group. Block randomisation was done with a web response platform. Participants and investigators were masked to treatment group allocation. Two intramuscular doses of vaccines were administered on day 0 (the day of randomisation) and day 14. Primary outcomes were solicited local and systemic reactogenicity events at 2 h and 7 days after vaccination and throughout the full study duration, including serious adverse events. Secondary outcome was seroconversion (at least four-fold increase from baseline) based on wild-type virus neutralisation. Cell-mediated responses were evaluated by intracellular staining and ELISpot. The trial is registered at ClinicalTrials.gov (NCT04471519).

FINDINGS

Between July 13 and 30, 2020, 827 participants were screened, of whom 375 were enrolled. Among the enrolled participants, 100 each were randomly assigned to the three vaccine groups, and 75 were randomly assigned to the control group (Algel only). After both doses, solicited local and systemic adverse reactions were reported by 17 (17%; 95% CI 10·5-26·1) participants in the 3 μg with Algel-IMDG group, 21 (21%; 13·8-30·5) in the 6 μg with Algel-IMDG group, 14 (14%; 8·1-22·7) in the 6 μg with Algel group, and ten (10%; 6·9-23·6) in the Algel-only group. The most common solicited adverse events were injection site pain (17 [5%] of 375 participants), headache (13 [3%]), fatigue (11 [3%]), fever (nine [2%]), and nausea or vomiting (seven [2%]). All solicited adverse events were mild (43 [69%] of 62) or moderate (19 [31%]) and were more frequent after the first dose. One serious adverse event of viral pneumonitis was reported in the 6 μg with Algel group, unrelated to the vaccine. Seroconversion rates (%) were 87·9, 91·9, and 82·8 in the 3 μg with Algel-IMDG, 6 μg with Algel-IMDG, and 6 μg with Algel groups, respectively. CD4⁺ and CD8⁺ T-cell responses were detected in a subset of 16 participants from both Algel-IMDG groups.

INTERPRETATION

BBV152 led to tolerable safety outcomes and enhanced immune responses. Both Algel-IMDG formulations were selected for phase 2 immunogenicity trials. Further efficacy trials are warranted.

FUNDING

Bharat Biotech International.

Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine, BBV152: a double-blind, randomised, phase 1 trial

BACKGROUND

To mitigate the effects of COVID-19, a vaccine is urgently needed. BBV152 is a whole-virion inactivated SARS-CoV-2 vaccine formulated with a toll-like receptor 7/8 agonist molecule adsorbed to alum (Algel-IMDG) or alum (Algel).

METHODS

We did a double-blind, multicentre, randomised, controlled phase 1 trial to assess the safety and immunogenicity of BBV152 at 11 hospitals across India. Healthy adults aged 18-55 years who were deemed healthy by the investigator were eligible. Individuals with positive SARS-CoV-2 nucleic acid and/or serology tests were excluded. Participants were randomly assigned to receive either one of three vaccine formulations (3 μg with Algel-IMDG, 6 μg with Algel-IMDG, or 6 μg with Algel) or an Algel only control vaccine group. Block randomisation was done with a web response platform. Participants and investigators were masked to treatment group allocation. Two intramuscular doses of vaccines were administered on day 0 (the day of randomisation) and day 14. Primary outcomes were solicited local and systemic reactogenicity events at 2 h and 7 days after vaccination and throughout the full study duration, including serious adverse events. Secondary outcome was seroconversion (at least four-fold increase from baseline) based on wild-type virus neutralisation. Cell-mediated responses were evaluated by intracellular staining and ELISpot. The trial is registered at ClinicalTrials.gov (NCT04471519).

FINDINGS

Between July 13 and 30, 2020, 827 participants were screened, of whom 375 were enrolled. Among the enrolled participants, 100 each were randomly assigned to the three vaccine groups, and 75 were randomly assigned to the control group (Algel only). After both doses, solicited local and systemic adverse reactions were reported by 17 (17%; 95% CI 10·5-26·1) participants in the 3 μg with Algel-IMDG group, 21 (21%; 13·8-30·5) in the 6 μg with Algel-IMDG group, 14 (14%; 8·1-22·7) in the 6 μg with Algel group, and ten (10%; 6·9-23·6) in the Algel-only group. The most common solicited adverse events were injection site pain (17 [5%] of 375 participants), headache (13 [3%]), fatigue (11 [3%]), fever (nine [2%]), and nausea or vomiting (seven [2%]). All solicited adverse events were mild (43 [69%] of 62) or moderate (19 [31%]) and were more frequent after the first dose. One serious adverse event of viral pneumonitis was reported in the 6 μg with Algel group, unrelated to the vaccine. Seroconversion rates (%) were 87·9, 91·9, and 82·8 in the 3 μg with Algel-IMDG, 6 μg with Algel-IMDG, and 6 μg with Algel groups, respectively. CD4⁺ and CD8⁺ T-cell responses were detected in a subset of 16 participants from both Algel-IMDG groups.

INTERPRETATION

BBV152 led to tolerable safety outcomes and enhanced immune responses. Both Algel-IMDG formulations were selected for phase 2 immunogenicity trials. Further efficacy trials are warranted.

FUNDING

Bharat Biotech International.

Developing a manufacturing process to deliver a cost effective and stable liquid human rotavirus vaccine

Despite solid evidence of the success of rotavirus vaccines in saving children from fatal gastroenteritis, more than 82 million infants worldwide still lack access to a rotavirus vaccine. The main barriers to global rotavirus vaccine coverage include cost, manufacturing capacity and suboptimal efficacy in low- and lower-middle income countries. One vaccine candidate with the potential to address the latter is based on the novel, naturally attenuated RV3 strain of rotavirus, RV3-BB vaccine administered in a birth dose strategy had a vaccine efficacy against severe rotavirus gastroenteritis of 94% at 12 months of age in infants in Indonesia. To further develop this vaccine candidate, a well-documented and low-cost manufacturing process is required. A target fully loaded cost of goods (COGs) of ≤$3.50 per course of three doses was set based on predicted market requirements. COGs modelling was leveraged to develop a process using Vero cells in cell factories reaching high titers, reducing or replacing expensive reagents and shortening process time to maximise output. Stable candidate liquid formulations were developed allowing two-year storage at 2-8 °C. In addition, the formulation potentially renders needless the pretreatment of vaccinees with antacid to ensure adequate gastric acid neutralization for routine oral vaccination. As a result, the formulation allows small volume dosing and reduction of supply chain costs. A dose ranging study is currently underway in Malawi that will inform the final clinical dose required. At a clinical dose of ≤6.3 log10 FFU, the COGs target of ≤$3.50 per three dose course was met. At a clinical dose of 6.5 log10 FFU, the final manufacturing process resulted in a COGs that is substantially lower than the current average market price, 2.44 USD per dose. The manufacturing and formulation processes were transferred to BioFarma in Indonesia to enable future RV3-BB vaccine production.

Research for Improving Patient Care

Research is an integral part of medicine. Health research aims at generating evidence for development of new medicines, procedures and tools, all of which are directed at improved patient care. Research also aims at incorporating this evidence into clinical practice by developing clinical practice guidelines and developing robust health systems including governmental policies and systems. Health research not only allows doctors to decide how to best treat patients but also empowers patients to take active role in their health.

The performance of licensed rotavirus vaccines and the development of a new generation of rotavirus vaccines: a review

Rotavirus, which causes acute gastroenteritis and severe diarrhea, has posed a great threat to children worldwide over the last 30 y. Since no specific drugs and therapies against rotavirus are available, vaccination is considered the most effective method of decreasing the morbidity and mortality related to rotavirus-associated gastroenteritis. To date, six rotavirus vaccines have been developed and licensed by local governments. Notably, Rotarix™ and RotaTeq™ have been recommended as universal agents against rotavirus infection by the World Health Organization; however, lower efficacies were found in less-developed and developing regions with medium and high child mortality than well-developed ones with low child mortality. For now, two promising novel vaccines, Rotavac™ and RotaSiil™ were pre-qualified by the World Health Organization in 2018. Other rotavirus vaccines in the pipeline including neonatal strain (RV3-BB) and several non-replicating rotavirus vaccines with a parenteral delivery strategy are currently undergoing investigation, with the potential to improve the performance of, and eliminate the safety concerns associated with, previous live oral rotavirus vaccines. This paper reviews the important developments in rotavirus vaccines in the last 20 y and discusses problems and challenges that require investigation in the future.

Immunogenicity, safety and reactogenicity of ROTAVAC® in healthy infants aged 6-8 weeks in Vietnam

BACKGROUND

ROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.

METHOD

We conducted a phase IV clinical trial in healthy infants aged 6-8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.

RESULTS

A total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.

CONCLUSIONS

The complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam.

Product review of the rotavirus vaccines ROTASIIL, ROTAVAC, and Rotavin-M1

Rotavirus is the leading cause of severe dehydrating gastroenteritis and death due to diarrhea among children under 5, causing over 180,000 under-5 deaths annually. Safe, effective rotavirus vaccines have been available for over a decade and are used in over 98 countries. In addition to the globally available, WHO-prequalified ROTARIX (GSK) and RotaTeq (Merck), several new rotavirus vaccines have attained national licensure - ROTAVAC (Bharat Biotech) and ROTASIIL (Serum Institute of India), licensed and manufactured in India and now WHO-prequalified, and Rotavin-M1 (PolyVac), licensed and manufactured in Vietnam. In this review, we summarize the available clinical trial and post-introduction evidence for these three new orally administered rotavirus vaccines. All three vaccines have demonstrated safety and efficacy against rotavirus diarrhea, although publicly available preclinical data are limited in some cases. This expanding product landscape presents a range of options to optimize immunization programs, and new presentations of each vaccine are currently under development.

Nanoparticles for mucosal vaccine delivery

Mucosal surfaces represent important routes of entry into the human body for the majority of pathogens, and they constitute unique sites for targeted vaccine delivery. Nanoparticle-based drug delivery systems are emerging technologies for delivering and improving the efficacy of mucosal vaccines. Recent studies have provided new insights into formulation and delivery aspects of importance for the design of safe and efficacious mucosal subunit vaccines based on nanoparticles. These include novel nanomaterials, their physicochemical properties and formulation approaches, nanoparticle interaction with immune cells in the mucosa, and mucosal immunization and delivery strategies. Here, we present recent progress in the application of nanoparticle-based approaches for mucosal vaccine delivery and discuss future research challenges and opportunities in the field.

Evidence of reduction of rotavirus diarrheal disease after rotavirus vaccine introduction in national immunization programs in the African countries: Report of the 11th African rotavirus symposium held in Lilongwe, Malawi

The 11th African Rotavirus Symposium was held in Lilongwe, Malawi from May 28th to 30th 2017. Over 270 delegates (73% from Africa) from 40 countries of which 30 (75%) were from African countries attended the symposium. Participants in this symposium included research scientists, clinicians, immunization managers, public health officials, policymakers and vaccine manufacturers. At the time of the symposium, 38 of the 54 (70%) countries in Africa had introduced rotavirus vaccines into their national immunization schedules. Delegates shared progress from rotavirus surveillance and vaccine impact monitoring, demonstrating the impact of the vaccine against rotavirus diarrheal hospitalizations. Data supported the beneficial effect and safety of WHO pre-qualified available vaccines up to 2017 (RotaTeq, Rotarix). This symposium highlighted the dramatic impact of the rotavirus vaccination, called for urgent adoption of these vaccines in remaining countries, particularly those with high disease burden and large birth cohorts (e.g. Nigeria, Democratic Republic of Congo) to attain the full public health benefits of rotavirus vaccination in Africa.

The 13th International Double-Stranded RNA Virus Symposium, Houffalize, Belgium, 24 to 28 September 2018

The triennial International Double-Stranded RNA Virus Symposium, this year organized by J. Matthijnssens, J. S. L. Parker, P. Danthi, and P. Van Damme in Belgium, gathered over 200 scientists to discuss novel observations and hypotheses in the field. The keynote lecture on functional interactions of bacteria and viruses in the gut microbiome was presented by Julie Pfeiffer. Workshops were held on viral diversity, molecular epidemiology, molecular virology, immunity and pathogenesis, virus structure, the viral use and abuse of cellular pathways, and applied double-stranded RNA (dsRNA) virology. The establishment of a plasmid only-based reverse genetics system for rotaviruses by several Japanese research groups in 2017 has now been reproduced by various other research groups and was discussed in detail. The visualization of dsRNA virus replication steps in living cells received much attention. Mechanisms of the cellular innate immune response to virus infection and of viral pathogenesis were explored. Knowledge of the gut microbiome's influence on specific immune responses has increased rapidly, also due to the availability of relevant animal models of virus infection. The method of cryo-electron microscopic (cryo-EM) tomography has elucidated various asymmetric structures in viral particles. The use of orthoreoviruses for oncolytic virotherapy was critically assessed. The application of llama-derived single chain nanobodies for passive immunotherapy was considered attractive. In a satellite symposium the introduction, impact and further developments of rotavirus vaccines were reviewed. The Jean Cohen Lecturer of this meeting was Harry B. Greenberg, who presented aspects of his research on rotaviruses over a period of more than 40 years. He was also interviewed at the meeting by Vincent Racaniello for the 513th session of This Week in Virology.

A Phase III open-label, randomized, active controlled clinical study to assess safety, immunogenicity and lot-to-lot consistency of a bovine-human reassortant pentavalent rotavirus vaccine in Indian infants

BACKGROUND

A heat-stable bovine-human rotavirus reassortant pentavalent vaccine (BRV-PV, ROTASIIL®) was developed in India. In this study, the vaccine was tested for safety, immunogenicity and clinical lot-to-lot consistency.

METHODS

This was a Phase III, open label, randomized, equivalence design study. The primary objective was to demonstrate lot-to-lot consistency of BRV-PV. Subjects were randomized into four arms, three arms received Lots A, B, and C of BRV-PV and the control arm, received Rotarix®. Three doses of BRV-PV or two doses of Rotarix® and one dose of placebo were given at 6, 10, and 14 weeks of age. Blood samples were collected four weeks after the third dose to assess rotavirus IgA antibody levels. The three lots of BRV-PV were equivalent if the 95% Confidence Intervals (CIs) of the geometric mean concentration (GMC) ratios were between 0.5 and 2. Solicited reactions were collected by using diary cards.

RESULTS

The study was conducted in 1500 randomized infants, of which 1341 infants completed the study. The IgA GMC ratios among the three lots were around 1 (Lot A versus Lot B: 1.07; Lot A versus Lot C: 1.06; and Lot B versus Lot C: 0.99). The 95% CIs for the GMC ratios were between 0.78 and 1.36. The IgA GMCs were: BRV-PV group 19.16 (95% CI 17.37-21.14) and Rotarix® group 10.92 (95% CI 9.36-12.74) (GMC ratio 1.75; 90% CI 1.51-2.04). Seropositivity rates were 46.98% (95% CI 43.86-50.11) and 31.12% (95% CI 26.17-36.41). The incidence of solicited reactions was comparable across the four arms. No serious adverse events were associated with the study vaccines, except two gastroenteritis events in the BRV-PV groups.

CONCLUSION

Lot-to-lot consistency of BRV-PV was demonstrated in terms of GMC ratios of IgA antibodies. The vaccine safety and immunogenicity profiles were similar to those of Rotarix®. Clinical Trials.Gov [NCT02584816] and Clinical Trial Registry of India [CTRI/2015/07/006034].