This is a Phase 1 open label study to evaluate the tolerability, safety, immunogenicity, and efficacy of SW1115C3, a neoantigen mRNA personalised cancer vaccine, in patients with advanced malignant solid tumours.

Inclusion Criteria:

• Are 18 to 80 years old (including boundary values), without limitation of sex at time of consent.
• Based on the RECIST 1.1 criteria for disease progression, (a maximum increase in tumour diameter of 20%) for participants undergoing prescreening who are receiving standard treatment, these participants may reach the defined disease progression criteria at the time of tumour vaccine administration.

Exclusion Criteria:

• Have used a live attenuated vaccine within 4 weeks before the first use of SW1115C3 with the following exceptions:
• Adverse reactions induced by previous anti-tumour treatments have not yet recovered to Grade ≤ 1 (except for toxicity evaluated to have no risk of safety by the PI [or designee], such as hair loss, Grade 2 peripheral neurotoxicity and hypothyroidism stabilised by hormone-replacement therapy) based on NCI CTCAE version 5.0.