CDSCO Asks Serum Institute to Revise Protocol for Trivalent Flu-COVID Vaccine Trial
New Delhi: The Subject Expert Committee (SEC) under the COVID-19 division of the Central Drugs Standard Control Organization (CDSCO) has reviewed a proposal submitted by Serum Institute of India Pvt. Ltd. (SIIPL) for a Phase II/III clinical trial of its Trivalent Nanoparticle Influenza Vaccine (NIV) and COVID-Influenza Combination (CIC) Vaccine, and has asked the firm to submit a revised study protocol incorporating additional design, safety, and statistical considerations.
The protocol, reviewed during the SEC meeting held on June 4, 2025, was titled:
“Phase II/III, multicentre, observer-blind, randomized, active-controlled study to evaluate immunogenicity and safety of a Trivalent Nanoparticle Influenza Vaccine and Covid-Influenza combination vaccine compared with Licensed Influenza and Covid-19 Vaccines in adults.”
The committee observed that the CIC vaccine leverages the baculovirus-insect cell platform also used in Novavax’s COVOVAX, which SIIPL had manufactured and distributed globally in over 200 million doses during the pandemic.
“Currently proposed Trivalent Influenza Nanoparticle Vaccine (tNIV) and Covid Influenza Vaccine Combination (CIC) are based on the same platform. CIC vaccine formulation contains both the SARS-CoV-2 and Influenza antigens,” the SEC noted.
In support of the proposal, the firm cited multiple international studies:
Over 4,300 participants took part in clinical trials for nanoparticle influenza vaccines (tNIV/qNIV), including adults aged >60 years in the U.S.
More than 2,100 participants were enrolled in Australia for the CIC vaccine trials combining COVID and influenza antigens.
“These trials demonstrated that CIC is safe and immunogenic... all doses were found safe,” the panel noted.
The investigational products used in all these trials were manufactured by SIIPL, further aligning the proposed Indian study with globally validated formulations.
However, the SEC has directed key changes before granting final approval to proceed:
“The study should be designed as four arm study with Covid Trivalent Influenza Combination (CIC) Vaccine, Trivalent Influenza Nanoparticle Vaccine, SARS-CoV-2 rs (JN.1 variant) and Fluquad.”
“Sample size of participants should be increased as per statistical calculation in proposed four arms with age stratification so that high-risk population (more than 55 years of age group) is appropriately considered for safety and immunogenicity analysis.”
“Cross-neutralization against VoCs for Covovax JN.1 alone and in CIC, immunogenicity persistence studies, efficacy end-points for hospitalization or severe COVID-19 cases should be part of exploratory objectives.”
Accordingly, the firm has been advised to submit a revised protocol incorporating all recommended modifications for further deliberation by the committee.
