A Study to Evaluate the Safety and Tolerability of Immunotherapy Combinations in Participants With Advanced Malignancies

Dose escalation of AB928 in combination with AB122 will be assessed in participants with
advanced malignancies. In this dose escalation combination study participants will receive
oral administration of AB928 as well as iv infusion of AB122.

Overall duration of treatment will depend on how well the treatment is tolerated. Treatment
may continue until unacceptable toxicity or progressive disease or other reasons specified in
the protocol.

Inclusion Criteria:

1. Male or female participants ≥ 18 years

2. Dose escalation only: Pathologically confirmed non-small cell lung cancer, squamous
cell carcinoma of the head and neck, renal cell carcinoma, breast cancer, colorectal
cancer, melanoma, bladder cancer, ovarian cancer, endometrial cancer, Merkel cell
carcinoma, or gastroesophageal cancer that is metastatic, advanced or recurrent with
progression for which no alternative or curative therapy exists or standard therapy is
not considered appropriate by the participant and treating physician (reason must be
documented in medical records).

3. Must have at least 1 measurable lesion per RECIST v1.1.

4. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1.

5. Must have received standard of care, including potentially curative available
therapies or interventions.

6. Confirm that an archival tissue sample is available and ≤ 6 months old; if not, a new
biopsy of a tumor lesion must be obtained.

7. Adequate organ and marrow function

8. Dose expansion only: Patients with advanced clear-cell RCC who must have relapsed
during anti-PD-1 monotherapy

9. Patients may have received up to 4 prior lines of therapy, including chemotherapy

Exclusion Criteria:

1. Use of any live vaccines against infectious diseases (eg, influenza, varicella) within
4 weeks (28 days) of initiation of investigational product.

2. Underlying medical conditions that, in the Investigator's or Sponsor's opinion, will
make the administration of investigational product hazardous (eg, interstitial lung
disease, active infections requiring antibiotics, recent hospitalization with
unresolved symptoms) or obscure the interpretation of toxicity determination or AEs,
or concurrent medical condition requiring the use of immunosuppressive medications or
immunosuppressive doses of systemic or absorbable topical corticosteroids.

3. Has known psychiatric or substance abuse disorders that would interfere with
cooperation with the requirements of the trial.

4. Is pregnant or breastfeeding or expecting to conceive or father children within the
projected duration of the study, starting with the pre-screening or screening visit
through 90 days after the last dose of AB928 in combination with AB122.

5. Any active autoimmune disease or a documented history of autoimmune disease, or
history of a syndrome that required systemic steroids or immunosuppressive
medications, except for vitiligo or resolved childhood asthma/atopy. Participants with
asthma who require intermittent use of bronchodilators (such as albuterol) will not be
excluded from this study.

6. Prior malignancy active within the previous year except for locally curable cancers
that have been apparently cured, such as basal or squamous cell skin cancer,
superficial bladder cancer or carcinoma in situ of the cervix, breast, or prostate
cancer.

7. a. Prior treatment with an anti-PD-L1, anti-PD-1, anti-CTLA-4, or other immune
checkpoint inhibitor or agonist as a monotherapy or in combination; b. Has had prior
chemotherapy, targeted small-molecule therapy, or radiation therapy within 2 weeks
prior to Day 1 or has not recovered (ie, ≤ Grade 1 or baseline) from AEs due to a
previously administered agent, except ≤ Grade 2 alopecia or ≤ Grade 2 neuropathy; c.
Prior treatment with mammalian target of rapamycin (mTOR) inhibitor.

8. Use of other investigational drugs (drugs not marketed for any indication) within 28
days or at least 5 half-lives (whichever is longer) before investigational product
administration.