Study of Radspherin® in Recurrent Ovarian Cancer Subjects With Peritoneal Carcinomatosis

Inclusion Criteria:

1. Able and willing to provide written informed consent and to comply with the clinicalstudy protocol

2. Age ≥ 18 years

3. Histologically confirmed epithelial ovarian, fallopian tube and primary peritonealcarcinoma

4. Platinum sensitive recurrences of ovarian carcinoma who are eligible for debulkingsurgery to R0.

5. AEs recovered to at least grade 1 from the effects (excluding alopecia) of any priormedical therapy for malignancy at time of first administration of Radspherin®

6. ECOG Performance Status Score of 0 - 1

7. Adequate renal function

• Creatinine ≤ 1.8 mg/dl (159 μmol/l) and

• calculated creatinine clearance using the Cockcroft-Gault formula ≥ 45 ml/min,or

• measured creatinine clearance ≥ 45 ml/min

8. Adequate hepatic function

• Serum bilirubin <1.5 x upper limit of normal (ULN)

• Aspartate transaminase (AST) and alanine transaminase (ALT) ≤ 3 x ULN

9. Adequate bone marrow function:

• Absolute neutrophil count (ANC) ≥ 1.5 x 10^9/l

• Platelets ≥ 100 x 10^9/l

• Haemoglobin ≥ 9 g/dL

10. Adequate coagulation tests: INR ≤ 1.5 x ULN

11. For females of childbearing potential, a negative pregnancy test must be documentedprior to enrolment

12. For females of childbearing potential who have a male partner: agreement to use twoadequate methods of contraception (e.g. barrier, intrauterine device, hormonalimplants, combined oral contraceptives or vasectomized partner), during thetreatment period and for at least 3 months after the last dose of IMP.

Exclusion Criteria:

1. Neuroendocrine tumors, or non-epithelial ovarian cancers (e.g. germ cell tumors,Sex-cord tumors)

2. Tumors of borderline malignancy

3. Other synchronous visceral metastatic lesions, symptomatic CNS metastases.Metastatic lymph nodes are acceptable, except thoracic lymph nodes.

4. Pregnant or lactating (nursing) women

5. Active infections requiring antibiotics, and/or physician monitoring or recurrentfever >38.0 ⁰C associated with a clinical diagnosis of active infection

6. Active liver disease with positive serology for active hepatitis B, hepatitis C orknown HIV

7. Administration of an investigational medicinal product within 28 days, or at least 5times the half-life, prior to enrolment

8. Concurrent administration of any cancer therapy other than planned study treatmentwithin 4 weeks prior to, and up to 4 weeks after the last study treatment

9. Another primary malignancy within the past 3 years (except for non-melanoma skincancer, cervical cancer in situ or in situ stage 1 synchronous endometrial cancer)

10. Concurrent congestive heart failure or prior history of New York Heart Association (NYHA) class III/IV cardiac disease

11. Any condition or illness that, in the opinion of the Investigator or the medicalmonitor, would compromise the safety of the subjects or interfere with theevaluation of the safety of the IMP

12. In the Investigator's opinion not able to comply with study procedures. Any medicalor psychological condition that would preclude participation in the study orcompromise the ability to give informed consent

13. Treatment with bevacizumab (Avastin®) within 5 weeks prior to CRS

14. Known hypersensitivity to any of the excipients in the study drug

15. Persons who have been placed in an institution under an official or judicial order

16. Persons who are dependent on the sponsor financially must be excluded fromparticipation

17. Persons with active SARS-CoV-2 infection must be excluded from participation