The primary purpose of this study is to identify the recommended phase 2 dose (RP2D\[s\]) and schedule(s) to be safe for JNJ-79635322 in Part 1 (dose escalation), and to characterize the safety and tolerability of JNJ-79635322 at the RP2D(s) selected and in disease subgroups in Part 2 (dose expansion).
Have a documented initial diagnosis of multiple myeloma according to International Myeloma Working Group (IMWG) diagnostic criteria
Part 1: Have relapsed or refractory disease, have been treated with a proteasome inhibitor, immunomodulatory drug (IMiD) agent, and an anti-CD38-based therapy for the treatment of multiple myeloma (MM),and should have been treated with at least 3 prior lines of therapy, or are refractory to proteosome inhibitor, IMiD agent, and an anti-CD38-based therapy regardless of prior lines of therapy, Part 2: Have relapsed or refractory disease, have been treated with a PI, IMiD and an anti-CD38 based therapy
Must have an Eastern Cooperative Oncology Group (ECOG) status of 0 or 1
Have measurable disease at screening as defined by at least 1 of the following: a) Serum M-protein level greater than or equal to (>=) 0.5 grams per deciliter (g/dL); or b) Urine M-protein level >=200 milligrams (mg)/24 hours; or c) Light chain multiple myeloma: Serum immunoglobulin (Ig) free light chain (FLC) >=10 milligrams per deciliter (mg/dL) and abnormal serum Ig kappa lambda FLC ratio; d) For participants without measurable disease in the serum, urine, or involved FLC, presence of 1 or more focus of extramedullary disease (EMD) which meets the following criteria: extramedullary plasmacytoma not contiguous with a bone lesion, at least 1 lesion >=2 centimeter [cm] (at its greatest dimension) diameter on whole body Positron Emission Tomography and Computed Tomography (PET-CT) Scans (or whole body magnetic resonance imaging [MRI] approved by sponsor), and not previously radiated (Part 2C participants are not required to have measurable disease)
Central Nervous System (CNS) involvement or clinical signs of meningeal involvement of multiple myeloma. If either is suspected, brain magnetic resonance imaging (MRI) and lumbar cytology are required
Active plasma cell leukemia, Waldenstrom's macroglobulinemia, POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes), or primary light chain amyloidosis
Received a cumulative dose of corticosteroids equivalent to greater than (>) 140 mg of prednisone within the 14-day period before the start of study treatment administration
Prior antitumor therapy as follows, in the specified time frame prior to the first dose of study treatment: (proteasome inhibitor [PI] therapy or radiotherapy within 14 days, immunomodulatory drug (IMiD) agent therapy within 7 days, gene-modified adoptive cell therapy within 90 days [not applicable for Part 2C participants], or CD3-redirecting therapy within 21 days[not applicable for Part 2B or 2C participants])