- Trial Phase
- Discontinued / Preclinical
- Time to Market
- Not estimable. Celgosivir has no active clinical development program, and the company has stated it is no longer in commercial development for its original indications. Any path to market would require a new clinical program, which has not been announced.
- Why 2/10
- Celgosivir has no scheduled hard, dated catalyst (PDUFA, pivotal readout, or AdComm) in the next 12 months. The drug is effectively not in active clinical development; the company's pipeline focus is on tafenoquine. ImpactScore is 2 because this is a minor/shelved program with no upcoming binary event.
Celgosivir has no scheduled clinical readouts or regulatory catalysts. The company's focus has shifted to tafenoquine for babesiosis and malaria, and to castanospermine (celgosivir's active metabolite) for tick-borne diseases via a Florida State University license. Any material move in SXTP from celgosivir would require the company to announce a new clinical program or partnership, which is not currently anticipated.
Price Chart
Executive Summary
Celgosivir is an oral antiviral prodrug (active metabolite: castanospermine) that inhibits host alpha-glucosidase I to disrupt viral envelope glycoprotein maturation. Originally developed by Migenix for hepatitis C, it was shelved after direct-acting antivirals made it obsolete. 60 Degrees Pharmaceuticals (NASDAQ: SXTP) now holds rights to it, but the company has confirmed celgosivir is no longer in commercial development for its original indications. The company's pipeline focus is on tafenoquine (ARAKODA) for malaria and babesiosis. Celgosivir's Phase 1b dengue trial (CELADEN) failed to show significant efficacy, and a planned Phase 1/2 trial was withdrawn. The company is instead pursuing castanospermine for tick-borne diseases via a Florida State University license. No active clinical trials or near-term catalysts exist for celgosivir.
How It Works
Celgosivir is an oral prodrug that converts in the body to castanospermine, a natural compound from the Australian black bean tree. It works by inhibiting an enzyme (alpha-glucosidase I) that viruses need to properly coat themselves with sugar molecules. By disrupting this process, celgosivir prevents viruses from maturing and replicating. It is a host-targeted antiviral, meaning it acts on human cells rather than directly on the virus, which could make it harder for viruses to develop resistance.
Trial Status
Celgosivir completed a Phase 1b proof-of-concept trial for dengue (CELADEN, NCT01619969) in 2013, which showed it was safe but did not significantly reduce viral load. A Phase 1/2 trial for dengue (NCT02569827) was withdrawn before enrollment. Development for hepatitis C was discontinued due to superior direct-acting antivirals. The company has stated celgosivir is no longer in commercial development for its original HIV and hepatitis C indications, though it lists viral disease as a pipeline area. No active clinical trials for celgosivir are registered on ClinicalTrials.gov as of October 2026.
The Two-Sided Case
Upcoming Catalysts
- None scheduled for celgosivir specifically. The company's next catalysts relate to tafenoquine for babesiosis, including potential January 2027 data readout from hospitalized babesiosis study (per Marketscreener).
Source Filing
The SecBot filing or press-release report that triggered this drug report:
Sixty Degrees Pharmaceuticals Press Release SXTP ·Originating report