Combination of SON-1010 (IL12-FHAB) and Atezolizumab in Patients With Platinum-resistant Ovarian Cancer

Inclusion Criteria:

1. Age ≥18 years at the time of informed consent
2. Part 1: Must have histologically or cytologically verified solid tumors and patientsmust have locally advanced or metastatic disease. Must have been treated with standardof care therapies for their disease and have no standard alternative treatment optionsthat are deemed by the treating physician to offer reasonable or potentially betterbenefit. Patients in cohorts C4, C5, and the RP2D expansion group must have PROC. Part 2: Must have PROC, defined as recurrence of OC within 6-months (180-days) afterthe last dose of a platinum-containing regimen), including epithelial, fallopian tube,or 1° peritoneal carcinoma. Patients may have had one or more alternative regimen(s)before this trial, including maintenance therapy between consecutive lines of therapy.Evidence of progression and the timing of progression or reoccurrence must refer tonew measurable disease by RECIST v1.1 or evaluable (non-measurable) disease. Thelatter is defined as not having measurable disease but has pre-study baseline valuesof CA125 at least 2 x ULN, with ascites and/or pleural effusion attributed to tumor ORwith solid and/or cystic abnormalities on radiographic imaging consistent withrecurrent disease that do not meet RECIST 1.1 definitions for target lesions.
3. Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1.
4. Adequate organ and bone marrow function, in the absence of growth factors.
5. Females of childbearing potential, or < 1-year postmenopause who are not permanentlysterile, must have a negative serum pregnancy test (beta-human chorionic gonadotropin [β-HCG]) at baseline, and agree to use 2 highly effective methods of birth controlduring the study and for 30 days after the last dose of study drug. Females who arenot of childbearing potential (have had a tubal ligation, hysterectomy, or bilateraloophorectomy, or are ≥ 1-year postmenopause) or have a partner who has had a vasectomydo not need to use contraception. A follicle stimulating hormone (FSH) level > 35 IU/Lat screening will be performed to confirm status. Refer to Section 8.2.7 for furtherdetail.
6. Males and their female partners must use a highly effective method of birth control iffemale partner(s) is of childbearing potential and must not donate sperm during thestudy and for 90 days after the last dose of study drug.
7. Willing and able to provide signed informed consent, which includes compliance withthe requirements and restrictions listed in the informed consent form (ICF) and inthis protocol.

Exclusion Criteria:

1. Known history of allergy to any component of study drug or a history of severeallergic/anaphylactic reaction.
2. Hospitalization for subacute bowel obstruction, other complications of the cancer, orany major surgery within 28 days prior to C1D1. Elective surgery is allowed ifrecovered.
3. Infection with HIV-1 or HIV-2 or a history of Kaposi sarcoma and/or MulticentricCastleman Disease.
4. Current active liver disease from any cause, including hepatitis A (hepatitis A virusIgM positive), hepatitis B (hepatitis B virus [HBV] surface antigen positive), orhepatitis C (hepatitis C virus [HCV] antibody positive, confirmed by HCV ribonucleicacid). Patients with HCV with undetectable virus after treatment are eligible (note:patients must have completed curative anti-viral therapy at least 4 weeks prior toscreening). Patients with a prior history of HBV are eligible if quantitative PCR forHBV DNA is negative (note: patients must have received HBV antiviral therapy for atleast 4 weeks prior to screening)
5. Pregnancy and/or lactation
6. Has received a live or live-attenuated vaccine within 30 days prior to the first doseof study drug. (Note: Administration of killed vaccines and COVID-19 vaccines that arenot live or live-attenuated are allowed if > 14 days.)
7. History of any active infection requiring systemic antibiotics, antivirals orantifungals, including COVID-19, within 14 days before the first dose of study drug.
8. Any acute noninfectious illness not resolved by14 days before day 1.
9. History of or known or suspected autoimmune disease (exception(s): patients withvitiligo, Type I diabetes, resolved childhood atopic dermatitis, hypothyroidism, orhyperthyroidism that is clinically euthyroid at Screening are allowed). Otherexceptions may be allowed following discussion with the Sponsor Medical Monitor forpatients who have not received treatment for their autoimmune disorder in the past 3years
10. Known active central nervous system metastases and/or carcinomatous meningitis.Patients with previously treated brain metastases may participate provided they areclinically stable for at least 4 weeks prior to study entry and have no evidence ofnew or enlarging brain metastases.
11. Unresolved toxicities from prior anticancer therapy, defined as not resolved tobaseline or to Grade 1 (NCI 2017), except for alopecia, peripheral neuropathy, andhypothyroidism secondary to prior therapy if currently being treated and clinicallyeuthyroid.
12. Receipt of any investigational agent or treatment within 21 days or 5 half-lives,whichever is shorter, before the first dose of study drug.
13. Any prior immunotherapy or treatment with checkpoint inhibitors within a period of 5half-lives (or 3 months, whichever is shorter) since the last dose of the therapy.
14. Use of systemic steroids > 10 mg/day prednisone (or equivalent) within 10 days ofenrollment, except for local (topical, nasal, or inhaled) steroid use. Limited dosesof systemic steroids (e.g., in patients with exacerbation of reactive airway disease)must have completed at least 10 days before enrollment. Steroid use to prevent IVcontrast allergic reaction or anaphylaxis in patients who have known contrastallergies is allowed at any time before enrollment.
15. Active known second malignancy with the exception of any of the following:

• Adequately treated basal cell carcinoma, squamous cell carcinoma of the skin, orin situ cervical cancer
• Adequately treated Stage I cancer from which the patient is currently inremission and has been in remission for ≥ 2 years;
• Low-risk prostate cancer with Gleason score < 7 and prostate-specific antigen < 10 ng/mL; or
• Any other cancer from which the patient has been disease-free for ≥ 2 years.

16. Use of biotin (i.e., vitamin B7) or supplements containing biotin higher than thedaily adequate intake of 30 μg (FDA 2019) (Note: Patients who switch from a high doseto a dose of 30 μg/day or less are eligible for study entry)
17. Any of the following within 6 months before Baseline Day 1:

• Myocardial infarction;
• Unstable angina;
• Unstable symptomatic ischemic heart disease;
• New York Heart Association (NYHA) class III or IV heart failure;
• Thromboembolic events (e.g., deep vein thrombosis, pulmonary embolism, orsymptomatic cerebrovascular events);
• Any other significant cardiac condition (e.g., pericardial effusion, restrictivecardiomyopathy, severe untreated valvular stenosis, long QTc syndrome, or severecongenital heart disease).