Company Announcements

Asher Bio Announces Clinical Trial Collaboration and Supply Agreement on Etakafusp Alfa (AB248) in Combination with Bispecific T-cell Engager in Patients with Small Cell Lung Cancer

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Jan. 8, 2025-- Asher Biotherapeutics, a biotechnology company developing precisely-targeted immunotherapies for cancer and infectious diseases, today announced a clinical trial collaboration and supply agreement with Amgen (NASDAQ:AMGN) to evaluate etakafusp alfa (formerly known as AB248), Asher Bio’s investigational CD8+ T cell targeted interleukin-2 (IL-2) immunotherapy, in combination with IMDELLTRA® (tarlatamab), Amgen’s DLL3-targeting Bispecific T-cell Engager (BiTE®) therapy, in patients with extensive-stage small cell lung cancer (ES-SCLC).

“This clinical trial collaboration and supply agreement with Amgen allows us to further expand on the Phase 1 results for etakafusp alfa in a new combination with IMDELLTRA® in a global Phase 1b study in ES-SCLC,” said Don O’Sullivan, Ph.D., Chief Business Officer of Asher Bio. “Based on emerging data to date, we believe etakafusp alfa has the potential to improve the efficacy of T cell engagers (TCEs) by selectively expanding the CD8+ T cell population, improving effector function, tumor infiltration and reversing TCE-induced T cell desensitization. We look forward to collaborating with Amgen to assess the potential for the novel combination to improve outcomes for patients with ES-SCLC.”

As part of this collaboration agreement, Amgen will sponsor and operationalize a global Phase 1b study to evaluate the safety and early efficacy of etakafusp alfa in combination with IMDELLTRA® in patients with ES-SCLC. Asher Bio will retain full ownership of etakafusp alfa and will supply Amgen with etakafusp alfa at no cost.

About SCLC
SCLC is one of the most aggressive and devastating solid tumor malignancies, with a median survival of approximately 12 months following initial therapy and a 3% five-year relative survival rate for ES-SCLC.1,2,3 Current second-line treatments impart a short duration of response (median DoR: 3.3–5.3 months) and limited survival (median OS: 5.8-9.3 months), while current third-line treatments for SCLC, which consist primarily of chemotherapy, yield a short median DoR of 2.6 months and a median OS of 4.4-5.3 months.4-8 SCLC comprises ~15% of the 2.4 million plus patients diagnosed with lung cancer worldwide each year.9-11 Despite initial high response rates to first-line platinum-based chemotherapy, most patients quickly relapse within months and require subsequent treatment options.13

About Etakafusp Alfa (AB248)
Etakafusp Alfa (AB248) is a novel CD8+ T cell selective IL-2, generated by fusing a reduced potency IL-2 mutein to an anti-CD8β antibody. It was specifically engineered to selectively and potently activate CD8+ T-cells which are the immune cells that drive anti-tumor efficacy, while avoiding natural killer (NK) cells, which can act as a pharmacological sink and contribute to toxicity, and regulatory T (Treg) cells, which are immunosuppressive. Asher Bio is currently evaluating etakafusp alfa in a Phase 1a/1b clinical trial, AB248-101. The trial consists of a dose escalation and expansion phase to investigate the safety, pharmacokinetics (PK), pharmacodynamics (PD), and anti-tumor activity of etakafusp alfa alone and in combination with pembrolizumab in subjects with locally advanced/metastatic solid tumors who failed prior therapies. Initial pharmacokinetic and pharmacodynamic data from the ongoing Phase 1a/1b clinical trial support etakafusp alfa’s proof of mechanism and activity with a highly differentiated clinical profile. Early data shows potent and selective CD8+ T cell activation without substantial changes to Treg and NK cell numbers and initial evidence of anti-tumor activity, including confirmed objective responses, with a generally well-tolerated safety profile. Please refer to www.clinicaltrials.gov (NCT05653882) for additional details related to this Phase 1a/1b clinical trial.

About Asher Bio
Asher Bio is a biotechnology company developing therapies to precisely engage specific immune cells to fight cancer and chronic viral infection. We utilize our proprietary cis-targeting platform to develop therapies engineered to overcome limitations of other immune-based treatments by selectively activating specific immune cell types with validated disease fighting functionality. Our candidates feature an antibody connected to a modified immunomodulatory protein, such as a cytokine. Our candidate design is intended to enable our candidates to selectively activate the desired immune cells and not other cells that contribute to toxicity or immune suppression. Our lead program etakafusp alfa (AB248), an IL-2 molecule specifically targeted to CD8+ effector T cells, is currently in Phase 1 trials for oncology. Our broader portfolio includes AB821, an IND-ready CD8-targeted IL-21 immunotherapy, and early-stage programs targeting CAR-T cells, myeloid cells and CD4+ T cells. Asher Bio was founded by Ivana Djuretic and Andy Yeung with support from Third Rock Ventures and is located in South San Francisco. For more information, please visit http://www.asherbio.com and follow us on X (formerly Twitter) @AsherBio and on LinkedIn.

1 American Cancer Society. Lung Cancer Survival Rates.
2 Paz-Ares L, Chen Y, Reinmuth N, et al. Durvalumab, with or without tremelimumab, plus platinum-etoposide in first-line treatment of extensive-stage small-cell lung cancer: 3-year overall survival update from CASPIAN. ESMO Open. 2022;7:100408.
3 Liu SV, Reck M, Mansfield AS, et al. Updated Overall Survival and PD-L1 Subgroup Analysis of Patients With Extensive-Stage Small-Cell Lung Cancer Treated With Atezolizumab, Carboplatin, and Etoposide (IMpower133). J Clin Oncol. 2021;39:619-630.
4 Trigo J, Subbiah V, Besse B, et al. Lurbinectedin as second-line treatment for patients with small-cell lung cancer: a single-arm, open-label, phase 2 basket trial. Lancet Oncol. 2020;21(5):645-654.
5Von Pawel J, Schiller JH, Shepherd FA, et al. Topotecan versus cyclophosphamide, doxorubicin, and vincristine for the treatment of recurrent small-cell lung cancer. J Clin Oncol. 1999;17(2):658-67.
6Von Pawel J, Jotte R, Spigel DR, et al. Randomized phase III trial of amrubicin versus topotecan as second-line treatment for patients with small-cell lung cancer. J Clin Oncol. 2014;32(35):4012-9.
7 Coutinho AD, Shah M, Lunacsek OE, et al. Real-world treatment patterns and outcomes of patients with small cell lung cancer progression after 2 lines of therapy. Lung Cancer. 2019;127:53-58.
8 Borghaei H, Pundole X, Anderson E, et al. Treatment patterns and outcomes in recent US clinical practice for SCLC patients after two prior lines of therapy. Presentation at World Conference on Lung Cancer 2023. September 9-12, 2023; Singapore, SGP. Poster #EP13.07-03.
9 Oronsky B, Abrouk N, Caroen S, et al. A 2022 Update on Extensive Stage Small-Cell Lung Cancer (SCLC). J Cancer. 2022;13:2945-2953.
10World Health Organization. Lung. 2020.
11 Sabari JK, Lok BH, Laird JH, et al. Unravelling the biology of SCLC: implications for therapy. Nat Rev Clin Oncol. 2017;14:549-561.

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Source: Asher Biotherapeutics