8-K: Tempest Therapeutics Presents Promising CAR-T Data

Tempest Therapeutics announced strong clinical data for its lead CAR-T therapy candidate, TPST-2003, showing a 100% complete response rate in certain patient groups.

Summary

• Tempest Therapeutics presented updated clinical data for its dual-targeting CAR-T therapy candidate, TPST-2003, at the ISCT 2026 Annual Meeting.
• The data includes results from two ongoing Phase 1 trials: REDEEM-1 for relapsed/refractory multiple myeloma (rrMM) and POEMS-1 for POEMS syndrome.
• TPST-2003 demonstrated a 100% complete response (CR) rate among 15 CAR-T-naive efficacy-evaluable patients across both trials.
• Specifically, 10 out of 10 evaluable patients in the REDEEM-1 trial achieved CR, and 5 out of 5 evaluable patients in the POEMS-1 trial achieved CR as measured by normalization of serum vascular endothelial growth factor levels (CRVEGF).
• The therapy showed a favorable safety profile in the REDEEM-1 trial, with no Grade >3 Cytokine Release Syndrome (CRS) or Immune Effector Cell-Associated Neurotoxicity Syndrome (ICANS).
• Across three studies, 44 patients have been treated with TPST-2003 to date.
• Median progression-free survival (PFS) was 23.1 months in the investigator-initiated trial (IIT) for rrMM, including patients with extramedullary disease (EMD).
• Tempest plans to meet with the FDA to discuss initiating a U.S. registrational study for TPST-2003 later this year.

Sentiment

Score: 8

Explanation: StockSavvy.ai views this as a highly positive development due to the strong efficacy and safety data presented for TPST-2003, indicating significant potential for the drug candidate.

Positives

• 100% complete response (CR) rate among 15 CAR-T-naive efficacy-evaluable patients across REDEEM-1 and POEMS-1 trials.
• 100% CR rate in 10 evaluable patients in the REDEEM-1 trial for relapsed/refractory multiple myeloma (rrMM).
• 100% CRVEGF rate in 5 evaluable patients in the POEMS-1 trial for POEMS syndrome.
• Favorable safety profile in REDEEM-1 trial with no Grade >3 CRS or ICANS.
• Overall Response Rate (ORR) of 100% (29/29) among CAR-T-naive evaluable patients with measurable disease across REDEEM-1 and prior IIT, including 18 patients with EMD.
• Median Progression-Free Survival (PFS) of 23.1 months in the IIT for rrMM, including patients with EMD.
• Potential to outperform first-generation single-targeting CAR-T therapies, especially in patients with EMD.
• Tempest plans to discuss initiating a U.S. registrational study with the FDA.

Negatives

• One patient in the REDEEM-1 trial who had previously received a BCMA-targeting CAR-T did not respond.
• The data presented is from Phase 1 trials, and further validation in larger registrational studies is required.
• The filing mentions the need for additional capital to fund planned programs and operations, and to continue as a going concern.

Risks

• Unexpected safety or efficacy data observed during future clinical trials.
• The possibility that results from prior clinical trials may not be predictive of future results.
• Clinical trial site activation or enrollment rates that are lower than expected.
• Loss of key personnel.
• Changes in expected or existing competition.
• Changes in the regulatory environment.
• Volatility and uncertainty in the capital markets for biotechnology companies.
• Unexpected litigation or other disputes.

Future Outlook

Tempest Therapeutics plans to meet with the FDA to discuss initiating a U.S. registrational study for TPST-2003 later in 2026. The company is developing a pipeline of advanced CAR-T cell therapy product candidates for cancer.

Management Comments

• "The results that we are presenting at ISCT this week support our belief that TPST-2003 could offer a life-saving option for patients with rrMM, and, if approved, may outperform first-generation single-targeting CAR-T therapies, in particular in patients with EMD."
• "We are excited by the potential to offer patients who have relapsed from multiple prior lines of therapy a treatment that may achieve up to complete remission of their cancer."
• "The observed safety profile (no Grade >3 CRS or ICANS), together with the consistency of responses observed in the REDEEM-1 trial continue to support Tempests plan to pursue its objective of meeting with the FDA to discuss initiating a U.S. registrational study later this year."

Industry Context

StockSavvy.ai notes that the presented data for TPST-2003 in relapsed/refractory multiple myeloma, particularly its 100% CR rate in CAR-T-naive patients and promising PFS in EMD patients, positions it as a potentially competitive therapy against existing BCMA-targeting CAR-T treatments like Abecma and Carvykti, especially given its dual-targeting mechanism addressing tumor heterogeneity.

Comparison to Industry Standards

• TPST-2003 demonstrated a 100% CR rate among 15 CAR-T-naive efficacy-evaluable patients, compared to typical CR rates in earlier phase trials for similar indications.
• The median PFS of 23.1 months for TPST-2003 in rrMM patients with EMD is notably longer than the 7.9 months reported for Abecma and 13.8 months for Carvykti in their respective trials (KarMMa and CARTITUDE-1).
• The safety profile of TPST-2003 in the REDEEM-1 trial (no Grade >3 CRS or ICANS) appears favorable when compared to the reported rates of Grade 3 CRS (up to 9.3% for Abecma, 4% for Carvykti) and Grade 3 ICANS (up to 4% for Abecma, 2% for Carvykti) in approved BCMA CAR-T therapies.
• The 100% ORR in CAR-T-naive evaluable patients with measurable disease across REDEEM-1 and the prior IIT is a strong indicator of efficacy, surpassing benchmarks often seen in late-stage trials for heavily pre-treated patients.

Stakeholder Impact

• Shareholders: Positive impact expected from promising clinical data potentially increasing the value of the company and its lead asset.
• Patients: Potential for a new, effective treatment option for relapsed/refractory multiple myeloma and POEMS syndrome, especially for those with extramedullary disease.
• Healthcare Providers: Data supports the potential use of TPST-2003 as a therapeutic option, informing treatment decisions.

Next Steps

• Meet with the FDA to discuss initiating a U.S. registrational study for TPST-2003 later in 2026.
• Continue enrollment in the REDEEM-1 Phase 2a trial.
• Advance other dual-targeting CAR-T pipeline programs.

Key Dates

Recommendation

The presented data for TPST-2003 shows a 100% CR rate in CAR-T-naive patients and a median PFS of 23.1 months, significantly outperforming existing therapies in EMD patients, coupled with a favorable safety profile. This strong clinical validation in a difficult-to-treat indication, along with the clear path towards a registrational study, presents a compelling investment opportunity.

Keywords

CAR-T therapy, TPST-2003, Multiple Myeloma, POEMS syndrome, Clinical Trial, Biotechnology, Oncology, Tempest Therapeutics