A Study of Amivantamab Subcutaneous (SC) Administration for the Treatment of Advanced Solid Malignancies

Inclusion criteria:

* Part 1 and Part 2: Participant must have histologically or cytologically confirmed solid malignancy that is metastatic or unresectable and which may derive benefit from epidermal growth factor receptor (EGFR) or mesenchymal-epidermal transition tyrosine kinase receptor/hepatocyte growth factor receptor (cMet) directed therapy. Eligible tumor types include non-small cell lung cancer (NSCLC), squamous cell carcinoma of the head and neck (SCCHN), hepatocellular cancer (HCC), colorectal cancer (CRC), renal cell cancer (RCC), medullary thyroid cancer (MTC), gastroesophageal cancer (GEC), mesothelioma, breast cancer (BC) and ovarian cancer (OC). Participants must have either progressed after prior standard of care therapy for metastatic disease, be ineligible for, or have refused all other currently available therapeutic options. In cases where participants refuse currently available therapeutic options, this must be documented in the study records.
* Participant must have Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
* A woman of childbearing potential must have a negative serum (beta-human chorionic gonadotropin \[beta-hCG\]) at Screening and a negative urine or serum pregnancy test within 24 hours before the first dose of study drug
* A woman must agree not to donate eggs (ova, oocytes) for the purposes of assisted reproduction during the study and for 6 months after receiving the last dose of study drug
* A man who is sexually active with a woman of childbearing potential must agree to use a condom and his partner must also be practicing a highly effective method of contraception (that is, established use of oral, injected or implanted hormonal methods of contraception; placement of an Intrauterine device \[IUD\] or Intrauterine system \[IUS\])

Exclusion criteria:

* Participant has uncontrolled inter-current illness, including but not limited to poorly controlled hypertension or diabetes, ongoing or active systemic infection (that is, has discontinued all antibiotics for at least one week prior to first dose of study drug), diagnosed or suspected viral infection (except Human immunodeficiency virus \[HIV\] positive participants with 1 or more of the following: a) not receiving highly active antiretroviral therapy; b) a change in antiretroviral therapy within 6 months of the start of screening; c) cluster of differentiation 4 (CD4)+ T-cell count less than \[\<\]350 per cubic millimeters \[mm\^3\] at screening; d) an acquired immunodeficiency syndrome-defining opportunistic infection within 6 months of the start of screening), or psychiatric illness/social situation that would limit compliance with study requirements, including ability to self-care for anticipated toxicities \[that is. rash or paronychia\]. Participants with medical conditions requiring chronic continuous oxygen therapy are excluded
* Participant has had prior chemotherapy, targeted cancer therapy, or treatment with an investigational anti-cancer agent within 2 weeks or 4 half-lives, whichever is longer, before the first administration of study drug; or participant has received prior immunotherapy within 6 weeks before the first administration of study drug. For agents with long half-lives, the maximum required time since last dose is 4 weeks. Toxicities from previous anticancer therapies should have resolved to baseline levels or to Grade 1 or less, (except for alopecia \[any grade\], Grade less than or equal to \[\<=\] 2 peripheral neuropathy, and Grade less than \[\<\] 2 hypothyroidism stable on hormone replacement). Autoimmune toxicities from previous immunotherapy must be fully resolved to baseline levels
* Participants with untreated brain metastases. Participants with locally treated metastases that are clinically stable and asymptomatic for at least 2 weeks and who are off or receiving low-dose corticosteroid treatment (\<=10 milligrams \[mg\] prednisone or equivalent) for at least 2 weeks prior to study treatment are eligible
* Participant has an active malignancy other than the disease under study requiring treatment
* Participant has leptomeningeal disease