TTX-080 HLA-G Antagonist in Subjects With Advanced Cancers

A Phase 1a/1b Dose Escalation/Expansion Study of TTX-080, an HLA-G Antagonist, as Monotherapy and in Combination With Pembrolizumab, Cetuximab or FOLFIRI Plus Cetuximab in Patients With Advanced Solid Refractory/Resistant Malignancies

TTX-080-001 is a Phase 1, open label, dose escalation and dose expansion clinical study to determine the safety, tolerability, and recommended Phase 2 dose of TTX-080 monotherapy (HLA-G inhibitor) and in combination with either pembrolizumab (PD-1 inhibitor), cetuximab (EGFR inhibitor) or FOLFIRI plus cetuximab (EGFR inhibitor) in patients with advanced refractory / resistant solid malignancies including metastatic colorectal cancer (mCRC) patients.

TTX-080 is a fully human mAb designed to block the interaction of HLA-G with its known ligands, ILT2 and ILT4 molecules. The Phase 1a was an open label, multicenter, dose escalation clinical trial to determine the safety, tolerability, MTD or OBD, and the RP2D of TTX-080 when administered as a single agent. The Phase 1b is a dose expansion of TTX-080 monotherapy and in combination with either pembrolizumab or cetuximab in adult subjects with advanced refractory/resistant solid malignancies, including Head and Neck squamous cell carcinoma (HNSCC), Non-Small Cell Lung Cancer (NSCLC), Colorectal cancer (CRC), triple negative breast cancer (TNBC), renal cell carcinoma (RCC), and acral melanoma. Additionally, the Phase 1b includes randomized arms with TTX-080 in combination with FOLFIRI plus cetuximab compared to FOLFIRI plus cetuximab in metastatic Colorectal cancer. The study will seek to evaluate the pharmacokinetics and immunogenicity of TTX-080, and characterize the anti-tumor activity of TTX-080 as a monotherapy and in combination with pembrolizumab, cetuximab or FOLFIRI plus cetuximab. Only arm 9 and 10 are currently open to enrollment.

Abbreviated Inclusion Criteria:

1. Subject with histological diagnosis of advanced/metastatic cancer [currently enrolling in CRC only]
2. Age 18 years or older, is willing and able to provide informed consent
3. Evidence of measurable disease
4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1 AND life expectancy of at least 12 weeks

Abbreviated Exclusion Criteria:

1. History of allergy or hypersensitivity to study treatment components. Subjects with a history of severe hypersensitivity reaction to any monoclonal antibody
2. Use of an investigational agent within 28 days prior to the first dose of study treatment and throughout the study
3. Receiving high-dose systemic steroid therapy or any other form of immunosuppressive therapy
4. History of severe autoimmune disease
5. Uncontrolled intercurrent illness or other active malignancy requiring ongoing treatment