A Study of Apalutamide Combined With GnRH Agonist in Participants With Androgen Receptor Positive Salivary Gland Carcinoma

Inclusion Criteria:

* Histologically confirmed salivary gland carcinoma (SGC) by local pathology
* Androgen receptor (AR) expressing SGC: Local testing of AR-positivity will be performed as standard of care for the eligibility confirmation. AR-positivity will be defined according to immunohistochemistry (IHC) staining of tumor tissue with at least 1 percent (%) of cell nuclei staining positive. Tissue should be available for the central confirmation of AR-positivity, but the central result of AR positivity will not be required for initiating the study intervention
* Locally advanced or recurrent/metastatic SGC
* Measurable lesion(s) according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1
* Eastern Cooperative Oncology Group (ECOG) performance status 0, 1 or 2

Exclusion Criteria:

* Treatment with any other investigational agent or participation in another clinical study with therapeutic intent within 30 days prior to first dose. Treatment with a drug that has a short half life (t1/2) (for example, less than \[\<\] 1 day) may be eligible in accordance with the discussion with the sponsor's medical monitor
* Radiographically confirmed brain metastases. In case of history of brain metastases that were previously treated and not recurred for at least 6 months, they are considered eligible
* Toxicities from previous anticancer therapies should have resolved to baseline levels or to Grade 1 or less (except for all grade alopecia, and for peripheral neuropathy, and hypothyroidism stable on hormone replacement therapy to be Grade 2 or less). If corticosteroids are administered for any reasons such as the management of toxicities due to prior therapies, the dose must be tapered until 10 milligram (mg)/day or less of prednisolone and contact the sponsor's medical monitor on an individual basis prior to the first dose
* Active or symptomatic viral hepatitis or chronic liver disease; ascites or bleeding disorders secondary to hepatic dysfunction
* History of seizure or any condition that may predispose to seizure (including, but not limited to, prior stroke, transient ischemic attack, or loss of consciousness less than or equal to \[\<=\] 1 year prior to first dose; brain arteriovenous malformation; or intracranial masses such as schwannomas and meningiomas that are causing edema or mass effect)
* Treatment with drugs known to lower the seizure threshold within 4 weeks prior to first dose
* Known or suspected contraindications or hypersensitivity to apalutamide, gonadotropin-releasing hormone agonist (GnRHa) analogues or any of the components of the formulations
* Received prior ADT including a GnRH analogue, AR blocker such as bicalutamide, enzalutamide or 17alpha-hydroxylase-17,20-lyase (CYP17) inhibitor such as abiraterone acetate etc. Chemotherapy, radiation, or surgery as part of curative intent therapy are allowed so long as prior therapy did not include ADT. Prior chemotherapy, targeted cancer therapy or immunotherapy within 1 week or 4 half-lives whichever is longer, before the first administration of study drug. For agents with long half-lives, the maximum required time since last dose is 2 weeks