Study of an Immunotherapeutic, DPX-Survivac, in Combination With Low Dose Cyclophosphamide & Pembrolizumab, in Subjects With Selected Advanced & Recurrent Solid Tumors

Key Inclusion Criteria:

* Subjects with advanced or metastatic solid tumours who have completed treatment with first line therapy:

1. Epithelial ovarian, fallopian tube, or peritoneal cancer
2. Hepatocellular carcinoma
3. Non-small cell lung cancer
4. Urothelial cancer
5. Microsatellite instability high solid tumours, other than the above indications
* Radiologic and/or biochemical evidence of disease progression
* Completion of pre-treatment tumour biopsy
* Must have measurable disease by RECIST v1.1
* Ambulatory with an ECOG 0-1
* Life expectancy ≥ 6 months
* Meet protocol-specified laboratory requirements

Key Exclusion Criteria:

* Chemotherapy or immunotherapy within treatment within 28 days of start of study treatment
* Radiotherapy within treatment within 2 weeks of start of study treatment
* Prior therapy with an anti-PD-1, anti-PD-L1, or anti PD L2 agent or with an agent directed to another stimulatory or co-inhibitory T cell receptor where subject was discontinued from that treatment due to a Grade 3 or higher immune-related toxicity
* For NSCLC subjects: Known EGFR mutations or ALK rearrangements
* Prior receipt of survivin-based vaccine(s) and/or immunotherapies
* Concurrent second malignancy other than non-melanoma skin cancer, cervical carcinoma in situ, or controlled bladder cancer
* Clinical ascites or pleural fluid that cannot be managed
* Malignant bowel obstruction or recent history of bowel obstruction
* For OvCa, subjects with any single lesion greater than 5 cm
* Autoimmune disease requiring treatment within the last two years (except replacement therapy)
* Recent history of thyroiditis
* Any history of (non-infectious) pneumonitis that required steroid therapy or current pneumonitis
* Presence of a serious acute or chronic infection
* Active CNS metastases and/or carcinomatous meningitis
* GI condition that might limit absorption of oral agents
* Allogenic tissue/solid organ transplant
* Other serious intercurrent chronic or acute illness, including myocardial infarction or cerebrovascular event within 6 months
* Ongoing treatment with steroid therapy or other immunosuppressive
* Receipt of live attenuated vaccines
* Acute or chronic skin and/or microvascular disorders
* Edema or lymphedema in the lower limbs \> grade 2
* Severe hypersensitivity (≥ Grade 3) to pembrolizumab