Sorrento Announces Positive Phase IIa Study Results of Abivertinib for the Treatment of Relapsed/Refractory Marginal Zone Lymphoma (R/R MZL) and Its Plan for a Pivotal Phase III Study

• Abivertinib is a novel Bruton’s tyrosine kinase (BTK) inhibitor that irreversibly targets BTK. BTK inhibitors are a large category in cancer treatment, with multiple indications and generating over $10.6 billion per year revenue in 2022.
• In this phase IIa study conducted in China, a total of 27 R/R MZL patients treated with Abivertinib were assessed and the overall response rate (ORR) was 59.3 % (16/27 patients) and among them, 3 patients had complete responses (CR) with a CR rate of 11.1% (3/27patients) and disease control rate (DCR) was 92.6%. To date, progression free survival (PFS) and duration of response (DOR) have not been reached.
• Sorrento has communicated with the China Health Authority (National Medical Products Administration or NMPA) regarding the design of a pivotal phase III registration study of R/R MZL in China.

SAN DIEGO, July 05, 2023 (GLOBE NEWSWIRE) -- Sorrento Therapeutics, Inc. (OTC: SRNEQ) today announced positive results from a China phase IIa study of Abivertinib on R/R MZL and its plan for a pivotal study.

Abivertinib is a pyrrolopyrimidine-based, mutant EGFR and BTK dual inhibitor with potential across multiple indications. BTK inhibitors are a large category in cancer treatment, with multiple indications and generating over $10.6 billion per year revenue in 2022.⁽¹⁾ Abivertinib inhibits BTK with IC50 value of 0.4 nM. Previously, a positive phase Ib study result of Abivertinib on B cell lymphoma was reported.⁽²⁾ The phase IIa study on R/R MZL, a rare type of B cell lymphoma, was conducted in China in 27 R/R MZL patients. Abivertinib showed significant treatment benefits in 27 patients who were relapsed or refractory after multiple lines of treatment with an ORR of 59.3% (11.1% CR and 48.2% partial responses). This ORR is higher than the ORR of Ibrutinib (46%), which was first approved for the treatment of R/R MZL.⁽³⁾ The DCR was 92.6% and to date, both PFS and DOR have not been reached. In the phase IIa study, Abivertinib was well-tolerated, and no severe bleeding, arrhythmia (atrial fibrillation/flutter) or hypertension were seen in these Abivertinib-treated patients. Given these early results, Abivertinib has a promising safety and efficacy profile to date, which has the potential for it to be preferable to the approved drug Ibrutinib.⁽³⁾ Sorrento has communicated with the NMPA, and a consensus has been reached for a pivotal phase III registration study for the treatment of R/R MZL. The pivotal study will be a multicenter phase III study to assess the efficacy and safety of Abivertinib for treatment of relapsed/refractory marginal zone lymphoma. Sorrento will continue communicating with the NMPA to finalize the phase III protocol.