This clinical study is to evaluate the safety, tolerability, pharmacokinetics (PK), and preliminary antitumor activity of IDP-001 in participants with advanced or metastatic squamous and non-squamous NSCLC and other squamous cell solid tumors (for example, head and neck, esophageal, cervical, cutaneous).

Inclusion Criteria:

• Eastern Cooperative Oncology Group (ECOG) performance status of 0-1
• Histologically-confirmed advanced, metastatic, or recurrent solid tumors that is not amenable to surgical resection or other approved therapeutic options
• Satisfy requirements for prior treatments per tumor type as outlined in the protocol
• Measurable disease per RECIST v1.1
• Participant willing to provide tumor biopsies
• Adequate organ function
• Agree to contraception requirements as outlined in the protocol
• Life expectancy greater than 12 weeks

Exclusion Criteria:

• Any clinically significant cardiac disease
• Any clinically significant corneal disorder
• Known, active, and uncontrolled hepatitis B virus (HBV), hepatitis virus (HCV) or human immunodeficiency virus (HIV), or uncontrolled chronic or ongoing infectious requiring intravenous treatment.
• Active significant neurologic disorders
• Requires home oxygen
• Active autoimmune disease
• History or active skin disease requiring frequent treatment
• History of major immunologic reaction to prior immunoglobulin G-containing agent
• Clinically significant ascites or liver disease
• Uncontrolled diabetes or diabetic neuropathy
• Active bleeding disorders
• Participation in a concurrent clinical study in the treatment period
• Pregnant or lactating or planning to become pregnant
• Known hypersensitivity to IDP-001 or any of its ingredients
• Unresolved toxicities from previous anticancer therapy
• Has had a seizure prior to Screening
• Prior solid organ transplant or allogeneic stem cell transplant
• Current endocrinopathy
• History of Stevens-Johnson syndrome or Toxic Epidermal Necrolysis
• History or interstitial lung disease (ILD) or pneumonitis requiring treatment with systemic steroids
• Stroke or transient ischemic attack prior to Screening
• Participant has any other condition or illness that, in the opinion of the Investigator, may compromise participant safety, compliance, or interfere with the conduct and evaluation of the current study.

Note: Other inclusion and exclusion criteria may apply.