A Study of Disitamab Vedotin in Previously Treated Solid Tumors That Express HER2

Inclusion Criteria:

* Cohort 1: Head and neck cancer (HNC)

  * Must have pathologically-documented carcinoma of the head and neck with primary tumor site arising from the oral cavity, salivary gland, oropharynx, hypopharynx, and larynx; tumors arising from the nasopharynx are excluded.
  * Unresectable locally recurrent or metastatic stage disease
  * Prior therapies:

    * Participants must have disease progression after treatment with a platinum-based therapy
* Cohort 2: Non-small cell lung cancer (NSCLC)

  * Pathologically documented NSCLC
  * Unresectable locally-advanced or metastatic stage disease
  * Prior therapies

    * Must have progressed during or after a platinum-based therapy for LA/metastatic disease or, within 6 months of platinum-based adjuvant, neoadjuvant, or concomitant chemoradiotherapy for early or locally-advanced stage disease
    * Must have received prior anti-PD(L)1 therapy, unless contraindicated
    * Participants with known AGAs must have received appropriate targeted therapy, where available.
    * No more than 2 prior lines of cytotoxic chemotherapy for advanced disease
* Cohort 3: Ovarian Cancer

  * Pathologically documented epithelial cancers of ovarian, fallopian tube, or peritoneal origin
  * Unresectable locally-advanced or metastatic stage disease
  * Prior therapies

    * Must have platinum resistant disease (6 months or less between the completion of platinum-based treatment and identification of recurrence)
    * Must not have received more than 4 lines of prior cytotoxic chemotherapies for advanced disease
    * Participants with known BRCA mutations are permitted, but participants must have received targeted therapy with a PARP inhibitor
    * May have received prior anti-PD(L)1 therapy
* Cohort 4: Endometrial Cancer

  * Must have pathologically documented adenocarcinoma of the endometrium
  * Must have unresectable locally-advanced or metastatic stage disease.
  * Prior therapies

    * Must have relapsed/progressed after at least one prior platinum-based chemotherapy for recurrent, metastatic or primary unresectable disease
    * Must not have received more than 3 lines of prior cytotoxic chemotherapies for advanced disease
    * May have received prior anti-PD(L)1 therapy
* HER2 expression of 1+, 2+, or 3+, as determined by local IHC testing on a fresh or archival tumor tissue. Note: Participants with HER2 mutations are eligible.
* Measurable disease per RECIST v1.1 criteria as assessed by the investigator
* Able to provide formalin-fixed, paraffin-embedded (FFPE) tumor tissue blocks (or freshly sectioned slides)
* Eastern Cooperative Oncology Group (ECOG) performance status score of 0 or 1

Exclusion Criteria:

* Prior treatment with an MMAE-containing agent.
* Known hypersensitivity to any excipient contained in the drug formulation of disitamab vedotin.
* History of another invasive malignancy within 2 years before the first dose of study intervention, or any evidence of residual disease from a previously diagnosed malignancy.
* Active untreated CNS or leptomeningeal metastasis