A new day
A fresh start
Driven to end the opioidoverdose epidemic
Mission:
To end the opioid overdose and addiction epidemic and offer hope to individuals, families, and communities devastated by this crisis.
CounterX Therapeutics is at the forefront of the battle against the opioid epidemic, exploiting cutting-edge biotechnology to develop life-saving therapeutics and vaccines. We combine scientific expertise with an experienced leadership team and a deep commitment to social impact. Our groundbreaking antibody therapies are designed to blunt the effects of opioids, risk of overdose and a provide a path to recovery. Additionally, our pioneering vaccine technology aims to prevent addiction relapse by blocking the euphoric effects of opioids and to empower individuals to maintain a long-term recovery.
Fentanyl is the leading cause of death of Americans aged 18-45
70%
of all drug overdose deaths 1
50-100 times
more potent than morphine2
2 mg
Can be lethal 2
80%
of people who injected drugs test positive for fentanyl, but only
18%
intended to take it 5
Prevalence of fentanyl found in other drugs
893
Non-fatal pediatric exposures to fentanyl in 2023
~1500%
Increase from 2015 6
Sources: 1. National Center on Health Statistics, CDC WONDER. 2. https://doi.org/10.1016/j.drugalcdep.2016.11.033 3. Facts about Fentanyl. 4. Prevalence of fentanyl in methamphetamine and cocaine – ScienceDirect. 5. Understanding intentionality of fentanyl use and drug overdose risk – ScienceDirect. 6. Nonfatal pediatric fentanyl exposures reported to US poison centers, 2015–2023
70%
of all drug overdose deaths 1
50-100 times
more potent than morphine 2
2 mg
Can be lethal 1
80%
of people who injected drugs test positive for fentanyl, but only
18%
intended to take it 5
Prevalence of fentanyl found in other drugs
893
Non-fatal pediatric exposures to fentanyl in 2023
~1500%
Increase from 2015 6
Sources:
1.National Center on Health Statistics, CDC WONDER.
2. https://doi.org/10.1016/j.drugalcdep.2016.11.033 3. Facts about Fentanyl. 4. Prevalence of fentanyl in methamphetamine and cocaine – ScienceDirect. 5. Understanding intentionality of fentanyl use and drug overdose risk – ScienceDirect. 6. Nonfatal pediatric fentanyl exposures reported to US poison centers, 2015–2023
CounterXCL™ Platform
Our proprietary CounterXCL™ discovery platform is focused on developing novel antibody therapeutics and vaccines to address opioid dependence. By leveraging immunology, chemistry, advanced bioengineering and artificial intelligence, we create targeted solutions to block the life-threatening effects of fentanyl, opioids and other drugs.
CounterXCL™ Platform
Our proprietary CounterXCL™ discovery platform is focused on developing novel antibody therapeutics and vaccines to address opioid dependence. By leveraging immunology, chemistry, advanced bioengineering and artificial intelligence, we create targeted solutions to block the life-threatening effects of fentanyl, opioids and other drugs.
Pipeline
CounterX Therapeutics is developing a pipeline of groundbreaking antibody therapeutics and vaccines to block the effects of opioids and save lives. Our differentiated therapies can potentially prevent overdose and empower individuals to initiate and maintain a long-term recovery.
CTRX-101:
Our lead product, CTRX-101, is a monoclonal antibody in development for the prevention of accidental overdose in high-risk patients. It is a long-acting subcutaneous injectable product that is not an opioid or controlled substance. CTRX-101 was well-tolerated in preclinical models with no serious adverse events when used in combination with other medications for opoids use disorder (OUD). It is not expected to cause opioid withdrawal and may be safe when used in combination with other medications. CounterX Therapeutics anticipates filing an Investigational New Drug Application (IND) with the FDA in late 2025.
How does it work?
Fentanyl and other opioids circulate through the body and quickly enter the brain. They primarily bind to µ-opioid receptors in the brain causing profound sedation, coma and ultimately hypoxia. Breathing slows and ultimately stops resulting in rapid death, usually within minutes.
CTRX-101 binds fentanyl in the circulation, blocks fentanyl distribution to the brain and blunts the life-threatening effects of fentanyl. CTRX-101 may provide an effective and safer approach to preventing accidental overdose in high-risk patients than currently available treatment options. CTRX-101 may also offer a novel approach to treating opioid use disorder.
Scientific Publications
Galbo-Thomma LK, Marecki C, Kim CM, Hiranita T, Taylor JR, Maguire DR, Hicks D, Gebo A, Khaimraj A, Baehr C, Pravetoni M, France CP. Psychopharmacology (Berl). 2025 Feb 5. doi: 10.1007/s00213-025-06751-9. PMID: 39907778
Rodarte J, Baehr C, Hicks D, McGovern M, Zhang Y, Silva-Ortiz P, Hannon B, Duddu S, Pancera M, Pravetoni M. ACS Omega. 2024 Oct 7;9(41):42506-42519. doi: 10.1021/acsomega.4c06617. PMID: 39431098
Khaimraj A, Baehr CA, Hicks D, Raleigh MD, Pravetoni M. J Immunol. 2024 Sep 1;213(5):663-668. doi: 10.4049/jimmunol.2400170. PMID: 39018496
Martinez S, Harris H, Chao T, Luba R, Pravetoni M, Comer SD, Jones JD. Expert Opin Investig Drugs. 2023 Mar;32(3):181-185. doi: 10.1080/13543784.2023.2187286. PMID: 36863002
Rodarte JV, Baehr C, Hicks D, Liban TL, Weidle C, Rupert PB, Jahan R, Wall A, McGuire AT, Strong RK, Runyon S, Pravetoni M, Pancera M. Structure. 2023 Jan 5;31(1):20-32.e5. doi: 10.1016/j.str.2022.11.008. PMID: 36513069
Hicks D, Baehr C, Silva-Ortiz P, Khaimraj A, Luengas D, Hamid FA, Pravetoni M. Hum Vaccin Immunother. 2022 Nov 30;18(6):2122507. doi: 10.1080/21645515.2022.2122507. PMID: 36194773
Baehr CA, Wu MM, Pandit SG, Arias-Umana J, AuCoin D, Pravetoni M. J Pharmacol Exp Ther. 2022 May;381(2):129-136. doi: 10.1124/jpet.121.001048. PMID: 35153198
Baehr C, Kelcher AH, Khaimraj A, Reed DE, Pandit SG, AuCoin D, Averick S, Pravetoni M. J Pharmacol Exp Ther. 2020 Dec;375(3):469-477. doi: 10.1124/jpet.120.000124. PMID: 32980813
Leadership Team
Exceptional team of world-renowned substance use disorder experts and biopharmaceutical executives
