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Updated: May 21, 2021

Since the beginning of the pandemic of COVID-19, the world has been scrambling around trying to understand more about COVID-19. Recommendations from the CDC, national policies have been turned upside down and even revised multiple times. The only unchanged and unfazed constant is that vaccines were being rushed into production. Rushing into production is it a bad or a good thing?

The development of vaccines produced against the COVID-19 virus has never seen a vaccine produced at such a speed. Ex-president Donald J. Trump coined the word "Operation Warp-Speed". As always Donald was good at giving names to his campaigns and name-calling people but the terms he used this time was very "Sci-fi" and appropriate. Pharmaceutical companies were driving themselves to be the first company to be the fastest producer of the COVID-19 vaccine. Some companies had significant gains and some lost the race. So far major companies like Moderna, Pfizer, and J&J (Johnson & Johnson) made the cut with good evidence. What about other vaccines like the UK Astrazeneca, Novavax, Russian Sputnik-V or the China Sinovac? How do they fair?

So how do we compare these vaccines? You need to be aware that most of these vaccines' efficacy is good on clinical trials and looks good on paper, however in reality they may fair differently when the vaccines reach the arms of the general public. Meaning a vaccine can show the efficacy of 95% on clinical trial but when it reaches the general public's arms, the efficacy may be lower or higher than the clinical trial.

Currently, 3 vaccines are approved by the FDA (Food and Drug Association) is Pfizer, Moderna, and Johnson & Johnson vaccines.

What are the phases of a clinical study?

The phases of the clinical study are to determine the efficiency, mechanism, metabolism, excretion, and safety of a drug or vaccine. Each phase is used to determine different objectives. In short, a clinical study which studies experimented drug on a population to evaluate the efficacy, mechanism, metabolism, excretion, and safety of a drug.

Can PLHIV or People Living with HIV take the COVID-19 Vaccine?

Since this vaccine is still new and is approved for emergency use. There is still limited data about people living with HIV taking the vaccines. However, there is a small HIV population included in the study for the Pfizer and Moderna vaccine.

Is the Pfizer COVID-19 vaccine safe for people living with HIV?

In order to know the safety profile of the Pfizer vaccine, you will have to understand the process of the Pfizer COVID-19 vaccine clinical study and the steps to approve the vaccine for use.

How was the Pfizer trial conducted?

The Pfizer trial included 120 people with HIV. The Pfizer study design for HIV patients was not initially included in Phase 1 but they entered the study later at Phase 2 and 3. The chart below shows the inclusion of participants living with HIV in Phase 2.

What are the criteria of the Pfizer COVID study to include people living with HIV?

The participants were people living with HIV with stable HIV disease defined as:

  1. Viral load <50 copies/mL (within 6 months)

  2. CD4 count >200cell/mm3 (within 6 months)

  3. On treatment (> 6 months)

Why did people living with HIV not included in the Phase 1 study but recruited later in Phase 2 and 3 study?

We have no clear picture of the reason why Pfizer did not include HIV-positive participants in the phase 1 trials.

Pfizer then amended their study to include PLHIV with chronic stable HIV into phases 2 and 3 to establish efficacy and safety. This is a bold and inclusive move of Pfizer for this special group because people living with HIV are also considered as a high-risk population of acquiring COVID-19.

How did Pfizer monitor people living with HIV after they were vaccinated?

The participants who were HIV positive were asked to keep an electronic diary about any local or systemic or reactivity to the vaccine. This information is directly transferred to the investigator and recorded. The participants were on follow-up at an interval for their HIV viral load and CD4 count. The intervals are:

  1. Day 1 (1st dose)

  2. D19-23 (2nd dose)

  3. D175-189 (from 2nd dose)

  4. D359-378 (from 2nd dose)

  5. D714-742 (from 2nd dose)

This process ensures the safety and early reporting of reactivity of the vaccine to those participants who are HIV-positive.

Is the Pfizer vaccine safe and effective for people living with HIV?

Yes. The Pfizer vaccine has been proven to be safe and effective. In the HIV-positive group, there were no reported life-threatening events or serious adverse reactions. Local swelling and redness were reported in their participants but nothing severe in the HIV-positive population. I will surely support the use of the Pfizer vaccine in people living with HIV if their disease is stable:

  1. Viral load <50 copies/mL (within 6 months)

  2. CD4 count >200cell/mm3 (within 6 months)

  3. On treatment (> 6 months)

Is the Moderna COVID-19 vaccine safe for people living with HIV?

In order to know the safety profile of the Moderna vaccine, you will have to understand the process of the Moderna COVID-19 vaccine clinical study and the steps to approve the vaccine for use.

How was the Moderna trial conducted?

The Moderna trial included 176 people with HIV. In that study, one HIV-positive person in the placebo group and none in the vaccine group developed symptomatic COVID-19. No unusual safety concerns were reported for people with HIV.

This Chart is Moderna's clinical study on the inclusion of people living with HIV. They included 176 participants who were living with HIV out of the total 30350 participants.

What is the efficacy of the Moderna vaccine for people living with HIV?

In the Moderna Trial ninety (90) HIV participants were vaccinated and eighty-six (86) HIV participants were given a placebo. After the second vaccine was given they were monitored for any incidence of Covid positivity. The ninety (90) HIV participants did not get COVID comparatively against the placebo group where one (1) out of eighty-sex (86) participants became infected with COVID.

This shows 100% efficacy of the vaccine in HIV positive to prevent infection of COVID. Nevertheless, I will highlight that the issue with this study is that the population of HIV-positive participants is too small to be substantial enough to claim that the vaccine is going to be 100% effective against COVID in HIV-positive patients.

I agree the vaccine can reduce the risk and severity of COVID to a certain degree. I think that the study may still require a larger population of HIV participants in the study to say for certain that it is going to be 100% effective against people living with HIV. If the population sample size is larger, then the study will be more accurate.

In short, more sample size (HIV-positive participants) means that there will be social contact with other people who may be carriers of COVID and thus this will increase the incidence rate. By having more incidence rates, we will be able to test the true effectiveness of the vaccine. A more comprehensive study can be done later on but in this crisis, we need to roll-out vaccines as soon as possible. Now this vaccine cannot be subjected to such measures of scrutiny because we are trying to stop a global pandemic and economic crisis. As long as the safety profile of the vaccine for people living with HIV is well established; everyone should get this vaccine into their arms.

This chart shows the cumulative incidence curves of people receiving placebo and the Moderna vaccine from the first day of randomization from 0-110days. The placebo arm shows a high occurrence of COVID infection after randomization in the group as compared to the vaccinated arm. Therefore the vaccinated arm fairs significantly better from the time of vaccination to 100-110 days from the first day of randomization in preventing COVID incidence.

My rationale is simple; if the vaccine works very well with a 95% effectiveness for the general population. The vaccine would benefit equally to the special group population like immunocompromised (HIV-positive) or those with comorbid. As highlighted in the box below the efficacy finding are consistent across various subgroups and those in the special group category.

Which vaccine should I choose if I am a person living with HIV?

Looking at the study of both Pfizer and Moderna, I am sure that both are good vaccines to take if you are living with HIV. Make sure you are a chronic stable HIV person before taking the vaccine or talk to your doctor before getting your shot.

Can I take switch between vaccines?

Pfizer and Moderna vaccines are different proteins. Pfizer uses nucleoside modified RNA (BNT162 RNA) and Moderna uses mRNA-1273. Both vaccines need two doses and if you started on a Pfizer vaccine, do not switch from a Pfizer to a Moderna vaccine. They are both different types of vaccines and should not be switched in between doses.

Can I consider other vaccines if Pfizer or the Moderna vaccine is not available in my country?

This question is a rather grey area as many other vaccines did not include any HIV-positive participants in their study. I do not think that there is a right or wrong if you are forced to get another vaccine other than Pfizer or Moderna, but you will need to consider this analogy.


HPV vaccines were previously used in women and girls. The preception that HPV is a women's disease has made HPV vaccines available for women and not for men. It was until much later that scientists noticed that men are also getting HPV and dying of HPV that there was a paradigm shift. Now we are vaccinating men for HPV. Due to insufficient data, we always assumed that women were the only ones affected by HPV and we only protected women against HPV. If we vaccinated boys and men against HPV earlier, then we will not be seeing so many deaths or morbidity caused by HPV amongst men.

Interpretation of the analogy of the HPV vaccine similarity to the COVID vaccine:

Due to limited data that HPV vaccines can be used for men, therefore we delayed vaccination for men. This causes mortality and morbidity to increase. This situation is the same for the COVID vaccine. Due to limited data that the other COVID vaccines can be used for people living with HIV, we should not delay vaccination in HIV-stable people in order to reduce mortality and morbidity.

Now is not the time to speculate about the future. The limited data shows that the vaccines are safe and effective for the general population and should do the same for you. Now if you think that only Pfizer and Moderna vaccines can only be used in people living with HIV then that is your right. But I think we should get the necessary information for your own decision making.

We should not limit the use of other vaccines for people living with HIV because the other COVID vaccines are not live vaccines but nucleic acid or protein vaccines. It should be relatively safe to use other vaccines despite other vaccine companies did not include HIV participants in their study. It is possible that years from now these vaccines will be studied in larger HIV participants and the outcome may show that it is safe and effective.

Live vaccines are contraindicated for people living with HIV because they are an alive form of bacteria or virus. When these live vaccines are injected into people living with HIV, this may cause an incomplete immune response to kill the live bacteria or virus. When the live bacteria or virus is not completely eliminated then the they have the possibility to cause disease or infection. Example: Mumps is a live virus and if injected into a person with a low immune response can cause mumps instead of preventing mumps because the virus gets activated when it is not completely killed by the immune system.

Since COVID vaccines predominantly nucleic acid or protein vaccines, then it should not be an issue to take other vaccines if the Pfizer or Moderna vaccine is not available in your country.

Of course, everyone wants to get the best vaccine available in the market but the question is can the supply chain meet the demand globally?

What are the take-home message and the summary of the COVID-19 vaccine and people living with HIV?

  1. Make sure that you are stable HIV:

    1. Viral load <50 copies/mL (within 6 months)

    2. CD4 count >200cell/mm3 (within 6 months)

    3. On treatment (> 6 months)

  2. Most COVID-19 vaccines are not live-vaccine and should be safe for people living with HIV.

  3. Do not switch or change your vaccine type. If you are using Pfizer then stick to Pfizer.

  4. Check your MySahjetera App for updates about your turn for vaccination (Available in Malaysia only) or you can also register here.

  5. If you have taken the vaccine and suffer from an adverse reaction to the vaccine. Use the MySahjetera App to report the adverse reaction or ask your family doctor to make a manual adverse reaction report to the Jabatan Pharmacy Malaysia (Department of Pharmaceutical Malaysia) Link:

  6. Sinovac (China vaccine) is a killed vaccine and should be relatively safe.

I will have another update about the Sinovac vaccine once I get more information about their research papers

You can only decide for yourself once you have gathered the information you need and make an educated decision.

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