New antidote for overdoses involving fentanyl and xylazine

A Novel Reversal Agent for Treatment of Overdose from the Combination of Fentanyl and Xylazine

NIH-funded research Clear Scientific, LLC · NIH-11159743

A new injectable medicine that quickly removes both fentanyl and xylazine to reverse sedation and breathing problems in people overdosing on these drugs.

Quick facts

Grant typeSbir 2 grant
Study typeNIH-funded research
Funding institutionClear Scientific, LLC NIH-funded
Lab location1 site (Cambridge, United States)
Project IDNIH-11159743 on NIH RePORTER

What this research studies

If I or someone I care about overdoses on fentanyl mixed with xylazine, researchers are developing an intramuscular antidote meant to quickly bind and remove both drugs, restore breathing, and reverse sedation. The drug is a small-molecule sequestrant that captures fentanyl and xylazine and speeds their clearance into urine, and it is intended to be compatible with naloxone when respiratory depression is present. In earlier work the team identified two promising candidate compounds and now plans advanced development steps including safety, dosing, and preclinical studies to prepare for human testing. The goal is an easy-to-administer injection that bystanders or clinicians could use to treat combined fentanyl–xylazine overdoses.

Who could benefit from this research

Good fit: Ideal candidates would be adults at risk of or experiencing overdoses involving both fentanyl and xylazine, with later trials likely enrolling people treated in emergency settings or other clinical sites.

Not a fit: People whose overdoses do not involve fentanyl or xylazine, or who have contraindications or allergies to the compound, may not receive benefit from this antidote.

Why it matters

Potential benefit: If successful, this could rapidly reverse sedation and breathing failure from combined fentanyl and xylazine overdoses and save lives where naloxone alone is insufficient.

How similar studies have performed: This sequestrant approach is relatively novel for fentanyl–xylazine mixtures; related cucurbituril-type compounds have shown preclinical promise but no established human rescue agent for xylazine currently exists.

Where this research is happening

Cambridge, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.