FOI release

Freedom of Information request (FOI 22/1087)

Published 17 January 2024

23rd November 2022

FOI 22/1087

Dear ,

Thank you for your request 22/1087 of 4th November, submitted under the FOIA.

1   In the article it states This medicinal product has been authorised under a so-called ‘conditional approval’ scheme. Can you please clarify what is meant by this and its criteria 

1. The PAR for the conditional marketing authorisation for the Moderna Spikevax bivalent Original/Omicron BA.1 (50 micrograms/50 micrograms)/mL dispersion for injection (PLGB 53720/0004) is published by MHRA, a link is provided below:

https://mhraproducts4853.blob.core.windows.net/docs/ce60c3eba417c19726286be297e61f624ac6e911

The PAR states the conditions under which a marketing authorisation has been granted and provides an explanation of what a conditional marketing authorisation means.

1. Are all doses (original 2 plus the 2 subsequent boosters all the same chemical formula) ?

2. Currently, there are two Spikevax vaccines authorised for adults and adolescents (≥ 12 years old) in GB.  One is the Original (based on the WA1 strain; Moderna’s first approved COVID-19 (Spikevax) vaccine) and another is a bivalent product.

Spikevax (the Original) is available in two strengths, used to give either a 100 microgram dose or a 50 microgram dose.

The new bivalent booster consists of 25 micrograms/dose of the original vaccine (based on the WA1 strain ) and 25 micrograms/dose based on the Omicron strain BA1.

Therefore, depending on the vaccine given, the four doses administered may not be of the same chemical formula.

1. Has the chemical formula in the Mrna [SIC] vaccines been changed for the BA 1 strain compared to the WA1 original strain ? or is it the same chemical formula ?

2. The mRNA sequence targeting the WA1 original strain and the BA 1 strain is different.

Moderna’s bivalent vaccine (Spikevax bivalent Original/Omicron BA.1 (50 micrograms/50 micrograms)/mL dispersion for injection) includes a combination of mRNA nucleotide sequences. This includes a modified mRNA nucleotide sequence derived from Omicron (CX-31302, also known as Imelasomeran), and CX-024414, also known as elasomeran; the modified mRNA nucleotide sequence derived from Spike protein of 2019-novel Coronavirus (SARS-CoV-2). This CX-024414 component of the bivalent vaccine sequence is the same as that used in the monovalent vaccine (Moderna’s first approved COVID-19 (Spikevax) vaccine).

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Yours sincerely

MHRA Customer Experience Centre Communications and engagement team Medicines and Healthcare products Regulatory Agency