COM701 in Subjects With Advanced Solid Tumors

This Phase 1 study evaluates the safety, tolerability, Pharmacokinetics (PK) and preliminary
clinical activity of COM701 an inhibitor of poliovirus receptor related immunoglobulin domain
containing (PVRIG) as monotherapy and in combination with a PD-1 inhibitor in subjects with
advanced solid tumors. Cohort expansion in subjects with the following select tumor types
(Non-Small cell lung cancer (NSCLC), Ovarian, Breast (including Triple negative breast cancer
(TNBC) and Endometrial cancer) evaluating COM701 monotherapy and in combination with a PD-1
inhibitor will be explored.

Key Inclusion Criteria:

- Subject has Eastern Cooperative Oncology Group (ECOG) performance status 0-1.

- Subjects who received prior immune-stimulatory antitumor agents, such as anti-PD-1,
anti-PD-L1, anti-CTLA-4, OX-40, CD137, etc. are eligible.

- Histologically or cytologically confirmed, locally advanced or metastatic solid
malignancy and has exhausted all the available standard therapy or is not a candidate
for the available standard therapy.

Select Tumor Types (COM701 monotherapy cohort expansion; COM701 in combination with a PD-1
inhibitor):

- Breast cancer (TNBC): Histologically confirmed incurable, advanced estrogen receptor-,
progesterone receptor-, and human epidermal growth factor receptor 2 (HER2)-negative
(triple-negative) adenocarcinoma of the breast, as defined by the American Society of
Clinical Oncology-College of American Pathologists (ASCO-CAP) guidelines. Disease
recurrence or progression during or after at least one systemic treatment that
included an anthracycline and/or a taxane in the neoadjuvant, adjuvant, or metastatic
setting. Subjects must have progressed after a poly ADP-ribose polymerase (PARP)
inhibitor for patients with deleterious or suspected deleterious germline breast
cancer susceptibility gene (BRCA) mutated metastatic breast cancer.

- Endometrial cancer: Subjects with locally advanced or metastatic endometrial cancer,
Disease recurrence or progression during or after prior therapy that included
platinum-based chemotherapy.

- Ovarian cancer: Disease recurrence or progression during or after prior therapy that
included: surgical resection, platinum agent, PARP inhibitor (for subjects with
deleterious or suspected deleterious germline BRCA-mutated advanced ovarian cancer or
as a maintenance therapy for subjects who have had complete or partial response to
platinum-based therapy).

- NSCLC: Documented stage IIIB or IV or recurrent NSCLC, Disease recurrence or
progression during or after prior treatment that included: platinum agent, targeted
therapy such as a TKI (if with biopsy-confirmed cytogenetic mutation eg EGFR, ROS,
BRAF).

- For Phase 1a monotherapy expansion and Phase 1b only: subject has at least one
measurable lesion that could be followed during the study according to RECIST v1.1.

Key Exclusion Criteria:

- Active autoimmune disease requiring systemic therapy in the last 2 years prior to the
first dose of COM701.

- Symptomatic interstitial lung disease or inflammatory pneumonitis.

- History of immune-related events that lead to immunotherapy treatment discontinuation.

- Untreated or symptomatic central nervous system (CNS) metastases.

- Impaired cardiac function or clinically significant cardiac disease, including any of
the following: a) Unstable angina pectoris ≤ 6 months prior to first scheduled dose of
COM701; b) Acute myocardial infarction ≤ 6 months prior to first scheduled dose of
COM701.