A Phase 3, Randomized, Double-Blind Study of MK-7684A in Combination with Etoposide and Platinum Followed by MK-7684A vs Atezolizumab in Combination with Etoposide and Platinum Followed by Atezolizumab for the First-Line Treatment of Participants with Extensive-Stage Small Cell Lung Cancer

1. Has histologically or cytologically confirmed diagnosis of ES-SCLC in need
of first-line therapy.
2. Has ES-SCLC defined as Stage IV (T any, N any, M1a/b/c) by the American
Joint Committee on Cancer, Eighth Edition or T3-T4 due to multiple lung nodules
that are too extensive or have tumor/nodal volume that is too large to be
encompassed in a tolerable radiation plan.
3. Is male or female, at least 18 years of age at the time of providing
documented informed consent.
4. Male participants are eligible to participate if they agree to the following
during the intervention period and for at least the time needed to eliminate
each study intervention after the last dose of study intervention. The length
of time required to continue contraception for each study intervention after
the last dose of the intervention is as follows:
- Etoposide, cisplatin, or carboplatin: 95 days
- Blinded study intervention: no contraception measures
• Refrain from donating sperm
PLUS either:
• Be abstinent from heterosexual intercourse as their preferred and usual
lifestyle (abstinent on a long-term and persistent basis) and agree to remain
abstinent
OR
• Must agree to use contraception unless confirmed to be azoospermic as
detailed below:
- Agree to use a male condom plus partner use of an additional contraceptive
method when having penile-vaginal intercourse with a WOCBP who is not currently
pregnant.
- Contraceptive use by men should be consistent with local regulations
regarding the methods of contraception for those participating in clinical
studies. If the contraception requirements in the local label for any of the
study interventions is more stringent than the requirements above, the local
label requirements are to be followed.
5. A female participant is eligible to participate if she is not pregnant or
breastfeeding, and at least one of the following conditions applies:
• Is not a WOCBP
OR
• Is a WOCBP and using a contraceptive method that is highly effective, with
low user dependency, or be abstinent from heterosexual intercourse as their
preferred and usual lifestyle (abstinent on a longterm and persistent basis)
during the intervention period and for at least the time needed to eliminate
each study intervention after the last dose of study intervention and agrees
not to donate eggs (ova, oocytes) to others or freeze/store for her own use for
the purpose of reproduction
during this period. The length of time required to continue contraception for
each study intervention after the last dose of the intervention is as follows:
- Etoposide, cisplatin, or carboplatin: 180 days
- Blinded study intervention: 5 months
The investigator should evaluate the potential for contraceptive method failure
in relationship to the first dose of study intervention.
- A WOCBP must have a negative highly sensitive pregnancy test within 24 hours
before the first dose of study intervention.
- If a urine test cannot be confirmed as negative, a serum pregnancy test is
required. In such cases, the participant must be excluded from participation if
the serum pregnancy result is positive.
- Additional requirements for pregnancy testing during and after study
intervention are in Section 8.3.6 of the protocol.
- The investigator is responsible for review of medical history, menstrual
history, and recent sexual activity to decrease the risk for inclusion of a
woman with an early undetected pregnancy.
- Contraceptive use by women should be consistent with local regulations
regarding the methods of contraception for those participating in clinical
studies. If the contraception requirements in the
local label for any of the study interventions is more stringent than the
requirements above, the local label requirements are to be followed.
6. The participant (or legally acceptable representative) has provided
documented informed consent/assent for the study. The participant may also
provide consent/assent for FBR. However, the participant may participate in the
study without participating in FBR.
7. Has measurable disease per RECIST 1.1 as assessed by the local site
investigator/radiology. Lesions situated in a previously irradiated area are
considered measurable if progression has been shown in such lesions. At least 1
lesion that meets the criteria for being measurable, as
defined by RECIST 1.1, must be appropriate for selection as a target lesion.
8. Submits a pretreatment archival tumor tissue sample or newly obtained core,
incisional, or excisional biopsy of a tumor lesion not previously irradiated
where such sample exists. Biopsy/tissue is preferred, but cytology sample by
fine needle aspiration is allowed. The
sample may be submitted after enrollment but must be submitted within 4 weeks
after randomization.
9. Has an ECOG performance status of 0 to 1 assessed within 7 days before
allocation/ randomization.
10. Has adequate organ function.
11. Has a predicted life expectancy of >3 months.

1. Is considered a poor medical risk due to a serious, uncontrolled medical
disorder or nonmalignant systemic disease. Examples include, but are not
limited to, uncontrolled major seizure disorder, unstable spinal cord
compression, or severe or life-threatening superior vena cava
syndrome.
2. Has received prior treatment (systemic therapy including investigational
agents, curativeintent radiotherapy, or curative-intent surgical resection) for
SCLC.
3. Is expected to require any other form of antineoplastic therapy for SCLC
while on study.
4. Has received a live or live-attenuated vaccine within 30 days before the
first dose of study intervention. Administration of killed vaccines are allowed.
5. Has received an investigational agent or has used an investigational device
within 4 weeks prior to the first dose of study administration.
6. Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid
therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other
form of immunosuppressive therapy within 7 days prior the first dose of study
medication.
7. Has a known additional malignancy that is progressing or has required active
treatment within the past 3 years.
8. Has known active CNS metastases and/or carcinomatous meningitis.
Participants with brain metastases may participate only if they satisfy all of
the following:
• Completed treatment (eg, whole brain radiation treatment, stereotactic
radiosurgery, or equivalent) at least 14 days before the first dose of study
intervention
• Have no evidence of new or enlarging brain metastases confirmed by
posttreatment repeat brain imaging (preferably using the same modality)
performed at least 4 weeks after treatment and within the screening period, and
• Are neurologically stable without the need for steroids at least 7 days
before the first dose of study intervention as per local site assessment.
9. Has a history of severe hypersensitivity reaction (>=Grade 3) to any study
intervention and/or any of its excipients (refer to the IB and/or approved
product label(s) for a list of excipients).
10. Has an active autoimmune disease that has required systemic treatment in
past 2 years (ie, with use of disease modifying agents, corticosteroids or
immunosuppressive drugs). Replacement therapy (eg, thyroxine, insulin, or
physiologic corticosteroid replacement therapy for adrenal or pituitary
insufficiency) is not considered a form of systemic treatment and is allowed.
11. Has a history of (noninfectious) pneumonitis/interstitial lung disease that
required steroids or has current pneumonitis/interstitial lung disease.
12. Has a known history of, or active, neurologic paraneoplastic syndrome.
13. Has an active infection requiring systemic therapy.
14. Has a known history of HIV infection. No HIV testing is required unless
mandated by local health authority.
15. Has a known history of Hepatitis B (defined as HBsAg reactive) or known
active Hepatitis C virus (defined as HCV RNA [qualitative] is detected)
infection.
16. Has a history or current evidence of any condition, therapy, or laboratory
abnormality that might confound the results of the study, interfere with the
participant's participation for the full duration of the study, or is not in
the best interest of the participant to participate, in the opinion of the
treating investigator.
17. Has a known psychiatric or substance abuse disorder that would interfere
with the participant's ability to cooperate with the requirements of the study.
18. Has had an allogenic tissue/solid organ transplant.
19. Has had major surgery within 3 weeks before receiving the first dose of
study intervention or has not recovered adequately from toxicity and/or
complications from an intervention prior to receiving the first dose of study
intervention.
20. Has symptomatic ascites or pleural effusion. A participant who is
clinically stable following treatment for these conditions (including
therapeutic thoraco- or paracentesis) is eligible.