Tango Therapeutics, Inc. 8-K

What Happened
Tango Therapeutics (filed 8-K on June 8, 2026; data cutoff May 28, 2026) announced initial safety and efficacy results from its Phase 1/2 combination trial of vopimetostat with RAS(ON) inhibitors from Revolution Medicines in patients with MTAP‑deleted, RAS‑mutant metastatic pancreatic ductal adenocarcinoma (PDAC) and some non‑small cell lung cancer (NSCLC) patients. In total 59 patients were treated across the vopimetostat + daraxonrasib and vopimetostat + zoldonrasib arms; the company provided response‑evaluable data for subgroups with at least 14 weeks of follow‑up and reported plans to advance the daraxonrasib combination into Phase 3 development for MTAP‑deleted pancreatic cancer.

Key Details

• Total treated: 59 patients (daraxonrasib arm: 20 PDAC, 5 NSCLC; zoldonrasib arm: 34 PDAC).
• Daraxonrasib (vopimetostat 200 or 250 mg QD + daraxonrasib 100 mg QD): 12 PDAC and 3 NSCLC patients were response‑evaluable. PDAC ORR = 92% (11/12; 9 confirmed), six‑month PFS = 90%, DCR = 100%. NSCLC ORR = 100% (3/3, all confirmed). No related grade 4/5 AEs; most AEs grade 1–2. No DLTs at vopimetostat 200 mg/daraxonrasib 100 mg; three DLTs in two patients at vopimetostat 250 mg/daraxonrasib 100 mg. No discontinuations due to AEs.
• Zoldonrasib (vopimetostat 200 or 250 mg QD + zoldonrasib 600 or 1200 mg QD): 27 PDAC patients response‑evaluable; ORR = 52%, six‑month PFS = 74%, DCR = 96%. Generally well tolerated; no related grade 4/5 AEs, no DLTs, no discontinuations.
• Company intends to initiate a Phase 3 randomized controlled trial in front‑line MTAP‑deleted pancreatic cancer (subject to regulatory feedback) and explore second‑line registration opportunities.

Why It Matters
These are preliminary, early‑phase clinical results showing high response rates in a small, heavily pretreated PDAC cohort for the vopimetostat + daraxonrasib combination and a signal of activity for the vopimetostat + zoldonrasib combination. For investors, the key takeaways are the company’s Phase 3 intent for the daraxonrasib combo (a major development milestone) and that safety was broadly manageable in these cohorts. The filing also includes standard forward‑looking disclaimers; results are interim and based on limited patient numbers, and further data and regulatory review will determine whether these findings translate into later‑stage success.