Tat OyiDrug Class: Therapeutic Vaccines Organization: Biosantech Phase of Development: I/IIa
(Compound details obtained from Treatment Action Group website,1 Biosantech website,2 and Retrovirology article3)
What is an investigational vaccine?
To learn more about investigational vaccines and investigational drugs, read the What is an Investigational HIV Drug? fact sheet.
What is Tat Oyi?
Tat Oyi is an investigational vaccine that is being studied as a therapeutic vaccine for HIV.4 A
HIV researchers are developing and testing therapeutic vaccines for various goals:
- To slow down the progression of HIV .
- To eliminate the need for (ART) while still keeping undetectable levels of HIV. (ART is the recommended treatment for HIV infection and involves using a combination of different HIV medicines to prevent HIV from replicating.)
- As part of a combination strategy that includes HIV medicines and a therapeutic vaccine to eliminate all HIV from the body.
The AIDSinfo fact sheet What is a Therapeutic HIV Vaccine? has more information on therapeutic HIV vaccines.6,7
The Tat Oyi vaccine contains a specific HIV that helps the body produce an immune response that can fight the .3,8
How are clinical trials of investigational vaccines conducted?
Clinical trials are conducted in phases. Each phase has a different purpose and helps researchers answer different questions.9
- Phase I trials: Researchers test an investigational vaccine in a small group of people (20–80) for the first time. The purpose is to evaluate its safety, identify side effects, and determine if the vaccine produces an immune response in the body.
- Phase II trials: The investigational vaccine is administered to a larger group of people (100–300). Researchers further evaluate the vaccine’s safety and ability to produce an immune response in the body. Some effectiveness data on the health benefits of the vaccine may also be collected.
- Phase III trials: The investigational vaccine is administered to large groups of people (1,000–3,000) to confirm its effectiveness, monitor side effects, compare it with standard or equivalent treatments, and collect information that will allow the investigational vaccine to be used safely.9,10
In most cases, an investigational vaccine must be proven effective and must show continued safety in a Phase III to be considered for approval by FDA for sale in the United States. Some vaccines go through FDA’s accelerated approval process and are approved before a Phase III clinical trial is complete. After a vaccine is approved by FDA and made available to the public, researchers track its safety in Phase IV trials to seek more information about the vaccine’s risks, benefits, and optimal use.9
Some clinical trials are categorized as "a" or "b," such as "Phase Ia" or "Phase IIb." These different subphases typically mean that a study is researching certain types of information or using a certain type of participant population.
In what phase of testing is Tat Oyi?
Tat Oyi has been studied in a Phase I/IIa clinical trial.3
What are some studies on Tat Oyi?
Study Names: EVATAT trial; NCT01793818
Status: This study has been completed.
- Participants were adults who had been on an ART regimen that included 3 HIV medicines for at least 12 months. Participants' ART regimens had not changed during the 3 months prior to the start of the study.
- For the last 12 months, participants had levels of less than 40 copies/mL. (Viral load is the amount of HIV in a blood sample.)
- Participants had CD4 counts greater than 350 cells/mm3 at the start of the study. During the previous 12 months, participants’ lowest CD4 counts were above 200 cells/mm3. (A is a laboratory test that measures the number of CD4 cells in a sample of blood and is an important indicator of immune function.)
For more details on the study mentioned above, see the Health Professional version.
What side effects might Tat Oyi cause?
One goal of HIV research is to identify new drugs that have fewer side effects. In the EVATAT trial (NCT01793818) of Tat Oyi mentioned above, 5 out of 46 study participants experienced a serious side effect. Of those 5 participants, only 1 had a side effect (facial pain) that was possibly related to the Tat Oyi vaccine. This side effect occurred 11 months after the participant received the vaccine and lasted for 1 week.3 Some participants in the study also reported pain at the site of the injection.8
Because Tat Oyi is still being studied, information on possible side effects of the vaccine is not complete. As testing of Tat Oyi continues, additional information on possible side effects will be gathered.
Where can I get more information about clinical trials studying Tat Oyi?
More information about Tat Oyi-related research studies is available from the AIDSinfo database of study summaries. Click on the title of any trial in the list to see the ClinicalTrials.gov trial summary and more information about the study.
How can I find more information about participating in a clinical trial?
Participating in a clinical trial can provide benefits. For example, a volunteer participant can benefit from new research treatments before they are widely available. Participants also receive regular and careful medical attention from a research team that includes doctors and other health professionals. However, clinical trials may also involve risks of varying degrees, such as unpleasant, serious, or even life-threatening side effects from the treatment being studied.9
Your health care provider can help you decide whether participating in a clinical trial is right for you. For more information, visit NIH Clinical Research Trials and You.
- Treatment Action Group website. Research toward a cure trials. Available at: http://www.treatmentactiongroup.org/cure/trials. Last accessed on May 9, 2018. [Archived at WebCite]
- Biosantech website. Research program Tat. Available at: http://www.biosantech.org/En/nos-programmes/programme-de-recherche-tat/. Last accessed on May 9, 2018. [Archived at WebCite]
- Loret EP, Darque A, Jouve E, et al. Intradermal injection of a Tat Oyi-based therapeutic HIV vaccine reduces of 1.5 log copies/mL the HIV RNA rebound median and no HIV DNA rebound following cART interruption in a Phase I/II randomized controlled clinical trial. Retrovirology. 2016 Apr 1;13:21. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4818470/. Last accessed on May 9, 2018.
- Frick M, Gaudino A, Harrington M, et al. Treatment Action Group. 2017 pipeline report. July 2017. Available at: http://www.pipelinereport.org/sites/default/files/2017%20Pipeline%20Report%20Final.pdf. Last accessed on May 9, 2018.
- The History of Vaccines website. The development of HIV vaccines. Available at: https://www.historyofvaccines.org/content/articles/development-hiv-vaccines. Last accessed on May 9, 2018.
- Smith PL, Tanner H, Dalgleish A. Developments in HIV-1 immunotherapy and therapeutic vaccination. F1000Prime Rep. 2014 Jun 2;6:43. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4047951/. Last accessed on May 9, 2018.
- Graziani GM and Angel JB. Evaluating the efficacy of therapeutic HIV vaccines through analytical treatment interruptions. J Int AIDS Soc. 2015 Nov 9;18: 20497. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4641978/. Last accessed on May 9, 2018.
- Escaich S. Tat Oyi-based candidate therapeutic vaccine: a successful Phase 1 clinical trial in HIV-1 infected patients. Abstract presented at: International Conference on Retroviruses and Novel Drugs; June 8-9, 2015; Chicago, IL. Available at: https://retrovirus.conferenceseries.com/abstract/2015/tat-oyi-based-candidate-therapeutic-vaccine-a-successful-phase-1-clinical-trial-in-hiv-1-infected-patients. Last accessed on May 9, 2018. [Archived at WebCite]
- National Institutes of Health (NIH). NIH clinical research trials and you. Available at: https://www.nih.gov/health-information/nih-clinical-research-trials-you. Last accessed on May 9, 2018.
- Hudgens MG, Gilbert PB, Self SG. Endpoints in vaccine trials. Stat Methods Med Res. 2004 Apr;13(2):89-114. Available at: http://faculty.washington.edu/peterg/Vaccine2006/articles/HudgensGilbertSelfSMMR.pdf. Last accessed on May 9, 2018.
- Biosantech. Evaluation on seropositive patients of a synthetic vaccine targeting the HIV Tat protein. In: ClinicalTrials.gov. Bethesda (MD): National Library of Medicine (US). Registered on February 14, 2013. NLM Identifier: NCT01793818. Available at: https://clinicaltrials.gov/ct2/show/NCT01793818. Last accessed on May 9, 2018.
Last Reviewed: May 9, 2018