Drugs / TOS-358
Trials 1
| Phase | Registry id | Dates | Indication | Sponsor | Status | Outcome |
|---|---|---|---|---|---|---|
| Phase 1 | NCT05683418 | Feb 2023 → Dec 2027 expected | hormone receptor-positive breast cancer | Totus Medicines | Recruiting | No outcome recorded |
News releases announcing trial results or a regulatory action · 5
| Date | Issuer | Release |
|---|---|---|
| 2026-05-06 | Totus Medicines | Results Totus Medicines Presents Early Phase 1b Clinical Data Demonstrating 100% Disease Control Rate and Class-Leading Safety for TOS-358 + Fulvestrant Doublet Therapy in HR+/HER2- Breast Cancer at ESMO Breast Cancer Annual Congress 2026 totusmedicines.com ↗
First presentation of combination data demonstrates 100% disease control rate and 89% clinical benefit rate in women, including PAM-experienced patients, with median time on therapy exceeding 24 weeks |
| 2026-03-18 | Totus Medicines | Results Totus Medicines Presents Phase 1a Clinical Data for TOS-358, a Covalent PI3Ka Inhibitor, at ESMO TAT 2026 totusmedicines.com ↗
Overall, TOS-358 demonstrated a 50% clinical benefit rate (CBR), 75% disease control rate (DCR), and 45% of patients remained on drug for more than 24 weeks. |
| 2026-01-06 | Totus Medicines | Results Totus Medicines to Present at the 44th Annual J.P. Morgan Healthcare Conference totusmedicines.com ↗
Achieved strong monotherapy clinical anti-tumor activity with encouraging signals of meaningful durability across multiple solid tumor types |
| 2025-01-10 | Totus Medicines | Results Totus Medicines Announces Successful Completion of a Phase 1 Dose-Escalation Study and Initiation of an Expansion Trial Evaluating TOS-358 and Appoints Zelanna Goldberg as Chief Medical Officer totusmedicines.com ↗
The Phase 1 study results to date have demonstrated 95% saturating target engagement of PI3Ka in patients, initial clinical activity with an unconfirmed complete response and no grade 3/4 toxicities at several low dose levels. |
| 2023-04-10 | Totus Medicines | Results Totus Medicines Announces Presentations at the Upcoming American Association for Cancer Research (AACR) Annual Meeting totusmedicines.com ↗
The drug has demonstrated the capability to achieve >95% inhibition of PI3Kα, essential for anti-tumor efficacy. |
All press releases naming this drug 8 releases
Evidence & citations 4 cited values
Every value below carries the sentence it was read from. 1 source stands behind the page.
| Field | Value | Cited text |
|---|---|---|
| Known as | TOS-358 | ClinicalTrials.gov intervention name — accepted as the source's own label NCT05683418 ↗ |
| Action | Inhibit | “PIK3CA covalent inhibitor” NCT05683418 ↗ |
| Route | Oral | “TOS-358 administered orally on once a day (QD) and twice daily (BID) schedules” NCT05683418 ↗ |
| Target | PIK3CA | “PIK3CA covalent inhibitor” NCT05683418 ↗ |