Atezolizumab, Carboplatin and Etoposide for the Treatment of Extensive Stage Small Cell Lung Cancer with Untreated, Asymptomatic Brain Metastases

Inclusion Criteria

• Written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization for release of personal health information prior to registration. NOTE: HIPAA authorization may be included in the informed consent or obtained separately
• Age >= 18 years with ability and willingness to provide informed consent
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• Histological confirmation of small cell lung cancer- extensive stage (SCLC) per Veterans Administration Lung Study Group (VALG)
• At least one untreated asymptomatic brain metastasis that is measurable by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 that has not been previously irradiated
• No prior treatment for metastatic disease. NOTE: A single cycle of chemotherapy (platinum/etoposide) with or without atezolizumab is allowed within 30 days prior to enrollment
• Treatment-free for at least 6 months since last chemo/radiotherapy, among those treated (with curative intent) with prior chemo/radiotherapy for limited-stage SCLC
• Any prior cancer treatment must be completed at least 6 months prior to registration and the subject must have recovered from all reversible acute toxic effects of the regimen (other than alopecia) to grade =< 1 or baseline. NOTE: a single cycle of chemotherapy (platinum/etoposide) with or without atezolizumab is allowed within 30 days prior to enrollment
• A concurrent diagnosis of a separate malignancy is allowed if clinically stable and does not require tumor-directed therapy
• Absolute neutrophil count (ANC) >= 1.5K/mm^3 without granulocyte colony stimulating factor (GCSF)
• Hemoglobin (Hgb) >= 9 g/dL (without transfusion)
• Calculated creatinine clearance >= 50 cc/min OR serum creatinine (Cr) < 1.5 x institutional upper limit of normal (ULN) * Cockcroft-Gault formula will be used to calculate creatinine clearance
• Bilirubin =< 1.5 x upper limit of normal (ULN) * Patients with known Gilbert disease who have serum bilirubin level =< 3x ULN may be enrolled
• Aspartate aminotransferase (AST) =< 2 x ULN without liver metastasis, =< 5 x ULN with liver metastasis
• Alanine aminotransferase (ALT) =< 2 x ULN without liver metastasis, =< 5 x ULN with liver metastasis
• Females of childbearing potential must have a negative serum pregnancy test within 3 days (72 hours) prior to enrollment. NOTE: Females are considered of childbearing potential unless they are surgically sterile (have undergone a hysterectomy or bilateral oophorectomy) or they are naturally postmenopausal for at least 12 consecutive months
• Females of childbearing potential and males must be willing to abstain from heterosexual activity or to use 2 forms of effective methods of contraception from the time of informed consent until 150 days (5 months) after treatment discontinuation
• Negative hepatitis B surface antigen (HBsAg) test, negative total hepatitis B core antibody (HBcAb) test, or positive total HBcAb test followed by a negative hepatitis B virus (HBV) deoxyribonucleic acid (DNA) test. The HBV DNA test will be performed only for patients who have a positive total HBcAb test. Testing required at screening only if results are not known
• Negative hepatitis C virus (HCV) antibody test, or positive HCV antibody test followed by a negative HCV RNA test. The HCV RNA test will be performed only for patients who have a positive HCV antibody test. A positive HCV ribonucleic acid (RNA) test is sufficient to diagnose active HCV infection in the absence of an HCV antibody test
• As determined by the enrolling physician or protocol designee, ability of the subject to understand and comply with study procedures

Exclusion Criteria

• Known active central nervous system (CNS) metastases which are symptomatic. CNS metastases are considered asymptomatic if the patient does not require high dose or escalating corticosteroids or anticonvulsant therapy. Steroid dose must be equivalent to 2 mg of dexamethasone or less daily * Prior steroid use as part of an anti-emetic regimen with chemotherapy is allowed * Patients must be on a stable dose of corticosteroid. No tapering or decreasing dose within 7 days of enrollment
• Leptomeningeal disease. Discrete dural-based metastases will be allowed without evidence of leptomeningeal disease
• Radiation therapy within 14 days prior to day 1 of cycle 1 day 1
• Treatment with any investigational drug within 28 days prior to cycle 1 day 1
• Known auto-immune conditions requiring systemic immune suppression therapy other than prednisone =< 10 mg daily (or equivalent)
• History of interstitial pneumonitis from any cause
• Concurrent severe and/or uncontrolled medical conditions which may compromise participation in the study as assessed by site investigator
• Current active infectious disease requiring systemic antibiotics, antifungal, or antiviral treatment on cycle 1 day 1. Patients receiving prophylactic antibiotics (e.g., for prevention of urinary tract infection or chronic obstructive pulmonary disease) are eligible
• Current use of medications specified by the protocol as prohibited for administration in combination with the study drugs. This includes patients with a condition requiring systemic treatment with either corticosteroids (> 10 mg daily prednisone equivalents) or other immunosuppressive medications within 14 days prior to cycle 1 day 1. Inhaled or topical steroids and adrenal replacement doses > 10 mg daily prednisone equivalents are permitted in the absence of active autoimmune disease. Patients who are receiving denosumab prior to enrollment must be willing and eligible to receive a bisphosphonate instead
• Pregnant or breastfeeding (NOTE: breast milk cannot be stored for future use while the mother is being treated on study)
• History of myocardial infarction, New York Heart Association (NYHA) class III or IV congestive heart failure, or unstable angina, cardiac or other vascular stenting, angioplasty, or surgery within 6 months prior to study enrollment
• Known history of human immunodeficiency virus (HIV) seropositivity or known acquired immunodeficiency syndrome (AIDS), testing not required at screening
• Requirement for ongoing anticoagulation with heparin, low molecular weight heparin, or other oral anticoagulant (coumadin, direct oral anticoagulant [DOAC])
• Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures (once monthly or more frequently). NOTE: Patients with indwelling catheters (e.g., PleurX) are allowed
• History of severe allergic, anaphylactic, or other hypersensitivity reactions to chimeric or humanized antibodies or fusion proteins
• Known hypersensitivity or allergy to biopharmaceuticals produced in Chinese hamster ovary cells or any component of the atezolizumab formulation
• History of allergic reactions to carboplatin or etoposide
• Intolerance of atezolizumab or other PD-1/PD-L1 axis drug(s), or any other antibody or drug specifically targeting T-cell co-stimulation or immune checkpoint pathways, including prior therapy with anti-tumor vaccines or other immune-stimulatory anti-tumor agents