Inclusion Criteria:
\- Participants must have histologically or cytologically documented SCLC (small cell lung cancer). Participants with either limited or extensive disease stage at the initial diagnosis, who have received at least one prior line of systemic therapy, are eligible.
i) For initial limited stage (LS) SCLC:.
A. Those who progressed or recurred after more than 6 months treatment-free interval following treatment of curative surgical resection, systemic therapy, or radiotherapy, and subsequently received at least one line of systemic therapy to treat the recurrence or progression, and then progressed, or were intolerant to the prior systemic therapy per the assessment of investigators, these participants will be eligible, or
B. Who progressed or recurred within 6 months after treatment of curative surgical resection, systemic therapy, or radiotherapy, no matter if these participants have received subsequent systemic therapy, these participants will be eligible.
ii) For initial extensive stage (ES) SCLC, participants must have received at least one line of platinum-based systemic therapy (with/without immunotherapy), and then progressed, or been intolerant to the prior systemic therapy per the assessment of investigators.
A. Note: 1) For ES-SCLC with only one line of platinum-based regimen as well as chemotherapy-free interval is more than 6months when progression, only when participants refuse or are ineligible for re-treatment with platinum-based doublet per the assessment of investigators, these participants will be eligible. 2) If participants receive re-treatment with a platinum-based regimen, it is considered a second line of therapy.
* Participants must have a life expectancy of ≥12 weeks.
* Participants must have at least 1 measurable lesion outside the central nervous system (CNS) by computed tomography (CT) or magnetic resonance imaging (MRI) per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) criteria.
* Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1.
Exclusion Criteria:
* Untreated symptomatic CNS metastases.
* Leptomeningeal disease.
* Pleural effusion which cannot be controlled with appropriate interventions.
* Malignancy-related superior vena cava syndrome.
* Participants with an active, known or suspected, autoimmune disease.
* Concurrent malignancy (present during screening) requiring treatment or history of prior malignancy active within 2 years prior to first study treatment.
* Unresolved toxicity from prior anti-tumor therapy.
* Prior treatment with an anti-fuc-GM1 therapy or any other drug specifically targeting fuc-GM1.
* Other protocol-defined inclusion/exclusion criteria apply.