CDSCO Panel Rejects Phase II Data for Reliance's RelCoVax COVID-19 Booster Over Immunogenicity Gap
New Delhi: The Subject Expert Committee (SEC) on COVID-19 vaccines, operating under the Central Drugs Standard Control Organisation (CDSCO), has rejected the Phase II clinical trial findings submitted by Reliance Lifesciences for its protein subunit COVID-19 vaccine candidate, RelCoVax, following a detailed scientific review.
The evaluation was carried out during the 01st/25th SEC meeting held on May 6, 2025, at CDSCO Headquarters, New Delhi.
Reliance Lifesciences submitted its proposal under file numbers BIO/PostAppr/2025/37220 and BIO/CT/23/000008, presenting a Phase II trial titled:
“A prospective, multi-center, randomized, open-label, active control, Phase II clinical study to evaluate immunogenicity, safety and tolerability of single heterologous booster dose of RelCoVax® (Protein Subunit Vaccine of Reliance Life Sciences against SARS-CoV-2 Virus) with Corbevax® (Protein Subunit Vaccine of Biological E Ltd. against SARS-CoV-2 Virus).”
The objective of the trial was to assess whether RelCoVax® could elicit an immune response comparable to Corbevax® when administered as a heterologous booster.
However, after a detailed deliberation, the SEC found that the vaccine did not meet the primary immunogenicity endpoint. As a result, the SEC concluded that RelCoVax® failed to demonstrate non-inferiority when compared to the reference vaccine and thus did not recommend the trial results for further regulatory consideration. It observed that;
"Immunogenicity results of the test vaccine did not meet the primary objective of the study as compared with the reference vaccine. The lower bound of 95% CI of difference in proportion of seroconversion rate in test v/s reference group did not meet the non-inferiority criteria of -10% as defined in the protocol. Hence, the vaccine did not demonstrate non-inferiority with the comparator vaccine."
Disclaimer: This website is primarily for healthcare professionals. The content here does not replace medical advice and should not be used as medical, diagnostic, endorsement, treatment, or prescription advice. Medical science evolves rapidly, and we strive to keep our information current. If you find any discrepancies, please contact us at corrections@medicaldialogues.in. Read our Correction Policy here. Nothing here should be used as a substitute for medical advice, diagnosis, or treatment. We do not endorse any healthcare advice that contradicts a physician's guidance. Use of this site is subject to our Terms of Use, Privacy Policy, and Advertisement Policy. For more details, read our Full Disclaimer here.
NOTE: Join us in combating medical misinformation. If you encounter a questionable health, medical, or medical education claim, email us at factcheck@medicaldialogues.in for evaluation.