Inclusion Criteria:

- Histological or cytological diagnosis of Small Cell Lung Cancer (SCLC), including
malignant pleural effusion that is extensive stage per the International Staging
System

- Performance status of 0 to 1 on the Eastern Cooperative Oncology Group (ECOG)
performance status schedule

- No prior systemic chemotherapy, immunotherapy, or biological therapy for SCLC

- Prior radiation therapy allowed to <25% of the bone marrow. Participants who have
received prior radiation to the whole pelvis or chest for the treatment of SCLC are
not eligible

- At least 1 unidimensionally measurable lesion meeting Response Evaluation Criteria in
Solid Tumors (RECIST) version 1.1

- Adequate organ function including the following:

- Adequate bone marrow reserve: absolute neutrophil count (ANC) ≥1.5 x 10^9/ liter
(L), platelets ≥100 x 10^9/L, and hemoglobin ≥9 grams/deciliter (g/dL)

- Hepatic: bilirubin ≤1.5 times the upper limit of normal (ULN), alkaline
phosphatase (AP), Serum alanine aminotransferase (ALT) and aspartate
transaminase (AST) ≤3.0 x ULN (AP, AST, and ALT ≤5 x ULN is acceptable if liver
has tumor involvement)

- Renal: calculated creatinine clearance (CrCl) ≥50 milliliters per minute
(mL/min) based on the standard Cockcroft and Gault formula

- Estimated life expectancy of at least 12 weeks

- For women: Must be surgically sterile, post-menopausal, or compliant with a medically
approved contraceptive regimen during and for 6 months after the treatment period;
must have a negative serum pregnancy test within 7 days before study enrollment. For
men: Must be surgically sterile or compliant with a contraceptive regimen during and
for 6 months after the treatment period

- Availability of a tumor tissue sample

- Able to swallow capsules

Exclusion Criteria:

- Currently enrolled in, or discontinued within the last 30 days from, a clinical trial
involving an investigational product or non-approved use of a drug or device, or
concurrently enrolled in any other type of medical research judged not to be
scientifically or medically compatible with this study

- Have previously participated in a study involving LY2940680

- Have previously received treatment with carboplatin or etoposide

- Have a mixed histological diagnosis of SCLC and Non-Small Cell Lung Cancer (NSCLC)

- Have a serious concomitant systemic disorder that, in the opinion of the
investigator, would compromise the participant's ability to adhere to the protocol

- Have an active infection [≥38.5 degrees Celsius and/or receiving Intravenous (IV)
antibiotic therapy]

- Have a serious cardiac condition

- Have had a prior malignancy other than SCLC, carcinoma in situ of the cervix, or
nonmelanoma skin cancer, unless that prior malignancy was diagnosed and definitively
treated at least 5 years previously with no subsequent evidence of recurrence.
Participants with a history of non-metastatic prostate cancer, including biochemical
relapse only, will be eligible even if diagnosed less than 5 years previously

- Symptomatic central nervous system (CNS) metastases and asymptomatic CNS metastases
requiring concurrent corticosteroid therapy. Treated stable CNS metastases are
allowed; the participant must be stable after radiotherapy for ≥2 weeks and off of
corticosteroids for ≥1 week

- Presence of clinically significant third-space fluid collections that cannot be
controlled prior to study entry

- Significant weight loss (that is, ≥10%) over the 6-week period prior to study entry

- Concurrent administration of any other antitumor therapy. An exception will be made
for non-metastatic prostate cancer participants continuing androgen blockade therapy
only or breast cancer participants continuing adjuvant antiestrogen therapy only (for
example, an aromatase inhibitor)

- Females who are breastfeeding

- Have corrected QT interval (QTc) of >470 millisecond (msec) on screening
electrocardiogram (ECG)

- Have received medications that are strong inhibitors of Cytochrome P450 3A4 (CYP3A4)
within 7 days prior to receiving study drug