HIV Vaccine Trials and Progress for 2021

After decades of research and clinical trials, it may be difficult to contend with the fact that there have been new vaccines for other more recent infectious diseases but not for HIV. The reasons are both numerous and complex.

For example, HIV has multiple variants that are constantly evolving. This is likely due to their ability to work around the immune system. As the virus “hides” itself in the body, it can spread unknowingly 1 to 2 weeks after exposure.

The success of non-vaccine prevention methods like PrEP have also created logistical and ethical difficulties in designing accurate trials for HIV vaccine efficacy.

While such challenges may seem discouraging, the fact is, the research and development of an HIV vaccine has actually seen significant progress.

Researchers found the most success to date in humans during the “RV144 Thai trial,” which ran from 2003 to 2009. This trial involved a two-dose vaccine and yielded an estimated 31 percent efficacy rate.

Furthermore, as we’ll discuss later, the perceived “failed” attempts at developing an HIV vaccine have led to stepping-stones in the creation of other vaccines that protect from different infectious diseases. One recent example is the COVID-19 vaccine.

Lessons from the RV144 trial have since been applied to numerous other HIV vaccine trials.

One potentially promising trial was known as the HVTN 702 (Uhambo) trial, which ran from 2016 to 2021. However, the data revealed even less efficacy than the RV144, possibly due to lower protein doses.

Still, the HVTN 702 trial led to the development of two new potential HIV vaccines that are currently undergoing clinical trials. These are known as the HVTN 706 (Mosaico) and HVTN 705 (Imbokodo) trials.

Both Imbokodo and Mosaico involve the use of two shots, each containing a different type of vaccine and given at specific monthly intervals over a 6-month period.

One key difference is regional, with Imbokodo involving women from five countries in Sub-Saharan Africa only. Mosaico, on the other hand, is testing in the United States as well as seven other countries.

Heading into 2022, researchers and developers will likely focus on the two late-stage trials discussed above —Mosaico and Imbokodo. It’s important to note that as of August 2021, Imbokodo did not show “sufficient protection against HIV in women,” according to the National Institutes of Health.

While there’s still a possibility that any one of these HIV vaccine trials could fail, they currently show the most promise.

Also, while HIV vaccine trials have partially led to the rise of COVID-19 mRNA vaccines, one company is set to start testing an mRNA version of a possible HIV vaccine. This trial is being led by Moderna and several universities, and is in recruitment status as of December 2021.

The Moderna mRNA vaccine could produce antibodies to help prevent multiple HIV variants, similar to Moderna’s mRNA COVID-19 vaccine. These “messengers” work with the immune system by creating protective proteins.

Since the Mosaico and Imbokodo vaccine trials are in the latter stages, there are currently no further recruitment opportunities available.

If you’re interested in possibly participating in the upcoming Moderna mRNA HIV vaccine trial, check out the requirements here and discuss them with your doctor.

Additionally, there are constantly new trials being developed for other aspects of HIV, including new medications, related health conditions, and more. You can keep track of the latest trials and recruitment opportunities on ClinicalTrials.gov.

Before declaring yourself a possible candidate for enrollment in a clinical trial, it’s important to talk with your doctor first.

While the creation of an HIV vaccine still has not come to fruition, scientists caution against any perceptions that suggests the decades of work has been wasteful.

Not only have researchers learned valuable information that has brought us closer to developing an HIV vaccine, but previous research and trials have also led to the invention of vaccines for other types of infectious diseases.

COVID-19 (caused by SARS-CoV-2) vaccines are one prominent example of this “spill-over” effect. The research process for HIV vaccines has also led to the development of vaccinations for other infectious diseases, such as:

• severe acute respiratory syndrome (also known as “SARS” or SARS-CoV-1)
• human papillomavirus (HPV)
• Ebola hemorrhagic fever (Ebola)
• Middle East respiratory syndrome (MERS)

The influenza (the flu virus) vaccine has helped lead to the development of the vaccines listed above.

Aside from research and development, the rapid creation of COVID-19 vaccines was also heavily dependent on collaborations. This includes companies, government agencies, clinical facilities, and scientific institutions. One such example is the partnership between Pfizer and BioNTech.

Researchers hope that the partnerships developed during the COVID-19 pandemic could potentially inspire similar collaborations in developing an HIV vaccine sooner, rather than later.

There’s currently no vaccine to help prevent HIV, but researchers believe that one is on the horizon.

Numerous encouraging developments made in 2021 — including two late-stage trials and a Moderna mRNA trial —will continue into 2022. Any next steps will be based on the possible successes and failures of these trials.

In the meantime, it’s important to use resources that are currently available, including PrEP and PEP medications, and practice safer sex with a condom or other barrier methods, especially in higher risk situations.

Talk with your doctor about how you can minimize your own personal risk, as well as any concerns you may have. Any health care provider licensed to write prescriptions can prescribe PrEP; specialization in infectious diseases or HIV medicine is not required. Also, under the affordable care act, PReP must be free under almost all healthcare plans.