PyridostigmineOther Names: Mestinon, PDG, Regonol, pyridostigmine bromide Drug Class: Immune Modulators Molecular Formula: C9 H13 N2 O2Br Registry Number: 101-26-8 (CAS) Chemical Name: 3-hydroxy-1-methylpyridinium bromide dimethylcarbamate Chemical Class: Carbamates Phase of Development: Pyridostigmine is in Phase II development as an HIV treatment.
(Compound details obtained from ChemIDplus Advanced,1 Treatment Action Group HIV TB HCV Pipeline Report 2018,2 and Current Neuropharmacology article3)
What is pyridostigmine?
Pyridostigmine is anthat is being studied to treat HIV .2 Pyridostigmine is also currently approved by the U.S. (FDA) to treat a condition called myasthenia gravis and to reverse the effects of muscle relaxants.4,5
As an investigational HIV therapy, pyridostigmine is categorized as an immune modulator.2(also called immunomodulators) are substances that help to activate, boost, or restore normal immune function.
Researchers are currently studying whether pyridostigmine added to(ART) can help a person with HIV increase their .6
Which clinical trials are studying pyridostigmine?
Study Name: NCT00518154
Status: This study has been completed.
Purpose: The purpose of this study was to evaluate whether adding pyridostigmine to ART would increase the CD4 count in individuals who had low CD4 counts despite having on ART.7
Study Name: NCT03312244
Status: This study is ongoing, but not recruiting participants.
Purpose: The purpose of this study is to evaluate whether adding pyridostigmine to ART can increase CD4 counts in individuals who have viral suppression on ART.6
For more details on the studies listed above, see the Health Professional version of this drug summary.
What side effects might pyridostigmine cause?
One goal of HIV research is to identify new drugs that have fewer side effects. In the NCT00518154 study discussed under the previous question, seven participants were enrolled to receive pyridostigmine in addition to ART. No side effects related to pyridostigmine were reported during the study.8
Additional information on side effects known to be associated with pyridostigmine can be found in the FDA-approved Full Prescribing Information for Mestinon.4
Because pyridostigmine is still being studied, information on possible side effects of the drug is not complete. As testing of pyridostigmine continues, additional information on possible side effects will be gathered.
Where can I get more information about clinical trials studying pyridostigmine?
More information about pyridostigmine-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.
Some clinical trials may be looking for volunteer participants. Your health care provider can help you decide whether participating in a NIH Clinical Research Trials and You.is right for you. For information, visit
- United States National Library of Medicine. ChemIDplus Advanced: Pyridostigmine bromide. https://chem.nlm.nih.gov/chemidplus/rn/101-26-8. Accessed January 10, 2019.
- Jefferys R. The research toward a cure and immune-based therapies pipeline. Treatment Action Group HIV TB HCV Pipeline Report 2018. http://pipelinereport.org/sites/default/files/pipeline_2018_cure_ibt_rj_web3.pdf. Accessed January 10, 2019.
- Colovic MB, Krstic DZ, Lazarevic-Pašti TD, Bondžic AM, Vasic VM. Acetylcholinesterase inhibitors: pharmacology and toxicology. Curr Neuropharmacol. 2013;11(3):315-335. doi:10.2174/1570159X11311030006
- Valeant Pharmaceuticals North America LLC. Mestinon: full prescribing information, June 6, 2017. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=a851795e-b7a8-40c3-9922-5e79d3eb4d92. Accessed January 10, 2019.
- Sandoz Inc. Regonol: full prescribing information, December 29, 2011. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=208af931-a44e-43bf-a265-8e08534dc55f. Accessed January 10, 2019.
- Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. Study of the role of peripheral acetylcholinesterase inhibitor pyridostigmine as immunomodulators in a population of patients living with human immunodeficiency virus infection. In: ClinicalTrials.gov. Bethesda (MD): National Library of Medicine (US). Registered April 1, 2017. NLM Identifier: NCT03312244. https://clinicaltrials.gov/ct2/show/NCT03312244. Accessed January 10, 2019.
- Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran. Pilot study of an ACh-E inhibitor upon immune activation markers in HIV-1 infected patients receiving highly active antiretroviral therapy (HAART) showing an incomplete immune response. In: ClinicalTrials.gov. Bethesda (MD): National Library of Medicine (US). Registered August 17, 2007. NLM Identifier: NCT00518154. https://clinicaltrials.gov/ct2/show/NCT00518154. Accessed January 10, 2019.
- Valdés-Ferrer SI, Crispín JC, Belaunzarán-Zamudio PF, et al. Add-on pyridostigmine enhances CD4+ T-cell recovery in HIV-1-infected immunological non-responders: a proof-of-concept study. Front Immunol. 2017;8. doi:10.3389/fimmu.2017.01301
Last Reviewed: January 15, 2019