Himalaya Therapeutics Announces Highlights of Recent Clinical Progress

• Mecbotamab vedotin (BA3011) Phase 2 part 1 interim results in NSCLC continue to show antitumor activity with additional patients enrolled
• HTBA3011 Undifferentiated Pleomorphic Sarcoma (UPS) enrollment in Phase 2 part 2 of study anticipated to begin by year-end
• CAB-CTLA-4 (HTBA3071) Phase 1 study ongoing in tumor types responsive to CTLA-4 inhibition with first two cohorts completed without Dose Limiting Toxicities (DLTs) or Serious Adverse Events (SAEs) reported

SAN DIEGO and SHANGHAI , Nov. 8, 2022 /PRNewswire/ -- Himalaya Therapeutics ("Himalaya"), a clinical-stage biopharmaceutical company focused on development and commercialization of a novel class of investigational antibody therapeutics for the treatment of solid tumor cancer, which are based on the Conditionally Active Biologics ("CAB") technology platform, today provided clinical program updates for both mecbotamab vedotin (HTBA3011) and ozuriftamab vedotin (HTBA3021) addressing multiple tumor types as well as updates on CAB-CTLA-4 (HTBA3071).

On November 3, Himalaya's collaboration partner, BioAtla, Inc. (NASDAQ: BCAB) publicly announced operational updates described below on the ongoing global clinical trials for HTBA3011, HTBA3021 and HTBA3071. These trials included patients from Greater China, where Himalaya has regional rights for the product candidates, and where lung cancer is both the most frequent cancer, and the cancer with the highest mortality rate.

"As our partner, BioAtla, continues to advance our common programs outside of China, while we do so inside Greater China, we are pleased to see continued validation of the CAB platform across the global trials of product candidates, with different targets and a wide range of indications, addressing major market needs for cancer therapeutics in China," said Brian Zhang, PhD, Himalaya's CEO.

Key Developments, Operational Updates and Upcoming Milestones

Phase 2 Trial of Mecbotamab Vedotin (HTBA3011, NCT03425279) in Patients with:

• AXL-positive NSCLC
• Part 1 of the trial ongoing in patients who have previously experienced failure of PD-1/L1, EGFR, or ALK inhibitor therapies (average failure 3 lines of therapy)
• 24 patients enrolled as of October 2022, with 14 efficacy-evaluable patients (12 in the non-squamous adenocarcinoma group and 2 in the squamous cell carcinoma group)
  In the non-squamous group, 4 PRs were observed in monotherapy (4 of 8, ORR 50%) and 1 CR was observed in combination therapy (1 of 4, ORR 25%)
• Following HTBA3011 in both monotherapy and in combination with nivolumab in advanced NSCLC patients, the safety profile continues to be differentiated, with no new safety signals observed
• Full interim data set of approximately 20 efficacy-evaluable patients anticipated by year-end
• AXL-positive Soft Tissue and Primary Bone Sarcomas
• Part 2 of the Phase 2 study:
  Initiating part 2 and anticipate study enrollment commencement by year-end; Osteosarcoma, synovial sarcoma, and liposarcoma cohorts met pre-defined criteria to advance into part 2 and we may pursue these indications post-UPS approval
• In refractory sarcomas, HTBA3011 in both monotherapy and in combination with nivolumab is generally well-tolerated with no new safety signals observed

Phase 2 Trial of Ozuriftamab Vedotin (HTBA3021, NCT03504488) in Patients with:

• ROR2-positive NSCLC
• Trial enrolling in patients who have previously experienced failure of PD-1/L1, EGFR or ALK inhibitor therapy
• Interim update anticipated in beginning of next year
• ROR2-positive Melanoma
• Trial ongoing in patients who have previously experienced failure of PD-1 therapy
• Anticipate initiating screening of patients with validated liquid biopsy by year-end
• ROR2-positive SCCHN
• Trial ongoing in patients who have previously experienced failure of PD-1 therapy alone or in combination with platinum therapy
• Actively screening patients; anticipate multiple patients dosed by year-end

Phase 1/2 Dose-Escalation Trial of CAB-CTLA-4 (HTBA3071) Across Multiple Solid Tumor Types responsive to CTLA-4

• Trial ongoing with first two cohorts completed without any DLTs or SAEs reported; third cohort (70mg) is on-going with DLT observation period anticipated to conclude by year end

Anticipate potential IND submissions for pre-clinical next generation CAB candidates in 2023 and beyond

Himalaya is a global clinical-stage biotechnology company that is advancing its deep pipeline of novel monoclonal antibody and other protein therapeutic product candidates through clinical trials. These have been designed to have more selective targeting, greater safety and efficacy, and more cost-efficient and predictable manufacturing than traditional antibodies. Its product candidates have been developed using CAB technology, which is protected by more than 500 issued and pending patents globally. Himalaya is the sole Greater China licensee of CAB technology derived product candidates.

Investor Contact:
Nicholas Desjardins
Himalaya Therapeutics
ndesjardins@himalayatherapeutics.com

SOURCE Himalaya Therapeutics SEZC