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No, Pfizer hasn’t warned that Covid vaccine carries risk of ‘births defects due to genetic manipulation’

A screenshot posted on Facebook in South Africa in November 2021 says a document by drug company Pfizer warns that its Pfizer-BioNTech Covid vaccine can cause “birth defects due to genetic manipulation”.

It reads: “Page 132 of Pfizer vaccine.. basically says no unprotected sex up to 28 days after 2nd dose due to reproductive safety risk.. this is for males and females ..births defects due to genetic manipulation.”

Below that is a blurry reproduction of part of a document that seems to read “Appendix 4: Contraceptive Guidance” and then “Male Participant Reproductive Inclusion Criteria”. It also provides a link to the document.

The Pfizer vaccine – named Comirnaty and also known as tozinameran or BNT162b2 – has been found to have a 90% efficacy rate in preventing Covid-19, and extremely high effectiveness in preventing serious Covid illness. Unlike traditional vaccines that use a weakened form of a virus, it uses messenger RNA. This builds the virus’s spike protein, prompting an immune system response.

The vaccine requires two doses. It was approved for use in Britain, Canada, Saudi Arabia, the USA and Mexico in December 2020. South African approval came in March 2021.

But did “page 132 of Pfizer vaccine” really warn that both men and women would have to practise safe sex for 28 days after the second Comirnaty shot because of the “reproductive safety risk” caused by “genetic manipulation”?


Report on Pfizer’s three-phase vaccine trial

The claim is fairly old, appearing on Twitter in December 2020 when the vaccine was first approved.

The link in the screenshot goes nowhere, but using keywords from the blurry text we were able to track down a document published on the Pfizer website in November 2020.

The document is not a medicine package insert warning of side effects. It’s a report titled  A Phase 1/2/3 Study to Evaluate the Safety, Tolerability, Immunogenicity, and Efficacy of RNA Vaccine Candidates Against COVID-19 in Healthy Individuals.

It details Pfizer’s three-phase clinical trial of its two candidate mRNA vaccines, BNT162b1 and BNT162b2. The trial found BNT162b2 to have fewer side effects, and it was selected as Comirnaty.

The portion of the report in the screenshot sets out contraceptive guidance for men and women taking part in the trial. It says that for 28 days after the second dose, the men must agree to not donate sperm and to use a condom during sex, and the women “of childbearing potential” must agree to use an “acceptable” form of contraception.

The guidance does say these measures are needed to “eliminate reproductive safety risk of the study intervention”. But nowhere does it mention “birth defects” or “genetic manipulation”.

And earlier in the report it says a benefit of mRNA vaccines is that they “do not carry the risks associated with infection and may be given to people who cannot be administered live virus (eg, pregnant women and immunocompromised persons)”. If the vaccine carried the risk of birth defects, Pfizer would not have said it could be given to pregnant people.

Contraception precaution standard in all trials of new drugs

The contraception requirement for people taking part in clinical trials of new drugs is standard, cautious practice. It is, for example, set out in research protocols developed by the US National Institute of Allergy and Infectious Diseases.

Contraception is necessary in testing any drug without a “proven safety record in pregnancy”, the institute told our fact-checking colleagues at Check Your Fact. This doesn’t mean the drug is not safe during pregnancy.

The US Centers for Disease Control lists the possible side effects of the Pfizer-BioNTech vaccine. These include pain and swelling at the site of injection, as well as tiredness, headache, muscle pain, chills, fever and nausea.

“These side effects are normal signs that your body is building protection and should go away within a few days,” it says.

And “birth defects due to genetic manipulation” does not appear in the CDC’s list of possible side effects.

Nor does it appear in a package leaflet on the vaccine produced by the UK Medicines and Healthcare Products Regulatory Agency.

The screenshot is false.

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