Inclusion Criteria

          1. Histological or cytological diagnosis of incurable, advanced/metastatic cancer For
             Phase Ia (dose escalation): Enriched for patients with tumours associated with p53
             mutation or loss of function:

               1. Colorectal cancer (CRC)

               2. High grade serious ovarian cancer (HGSOC)

               3. Non small-cell lung cancer (NSCLC, squamous cell variant)

               4. Squamous carcinoma of the oesophagus

               5. Squamous carcinoma of the head and neck (HPV negative)

               6. urothelial cancer

               7. Breast cancer (triple negative type)

               8. Pancreatic cancer

             For Phase Ib (expansion cohorts): These will exclusively be CRC/mCRC, HGSOC and/or
             squamous NSCLC patients.

          2. Life expectancy of at least 12 weeks.

          3. Written (signed and dated) informed consent and be capable of complying with the
             protocol for the duration of the study, including hospital visits for treatment and
             scheduled follow-up visits and examinations.

          4. World Health Organisation (WHO) performance status of 0 or 1

          5. Haematological and biochemical indices within the ranges shown below. These
             measurements must be performed within one week before the patient starts study
             treatment (single dose given C1D-6 to C1D-11):

             Laboratory Test Value required

             Haemoglobin (Hb) ≥9.0 g/dL (no prior transfusion) or

               -  10.0 g/dL (transfusion within last 4 weeks)

             Absolute neutrophil count ≥1.5 x 10^9/L

             Platelet count ≥100 x 10^9/L

             Serum bilirubin ≤1.5 x upper limit of normal (ULN)

             Alanine amino-transferase (ALT) and aspartate amino-transferase (AST) ≤ 2.5 x (ULN)
             (or ≤5 x ULN in the presence of liver metastasis)

             Either:

             Calculated creatinine clearance (using the Wright or C&G formula) > 50 mL/min

             Or: Isotope clearance measurement** ≥ 50 mL/min (uncorrected) INR or PTT*** ≤1.5 x
             ULN Albumin ≥ 80% of the lower limit of normal

             ** Isotope clearance result to be used to confirm eligibility if calculated
             C&G/Wright method results in GFR of = 50 mL/min.

             *** Therapeutic INR values (2.0-3.0) are acceptable to confirm eligibility for
             patients who are taking concomitant warfarin

          6. Age 18 years or over.

          7. Consent must be given for use of archived tumour samples, pre and post treatment skin
             biopsies and hair follicle collection in all patients.

          8. Consent for pre and post treatment metastatic site tumour biopsies must be given for
             expanded cohorts but is optional for dose escalation cohorts.

        Exclusion Criteria:

          1. Radiotherapy (except for control of symptoms where irradiated lesions will not be
             followed for response), endocrine therapy, immunotherapy or chemotherapy during the
             previous 4 weeks (6 weeks for nitrosureas, Mitomycin-C).

          2. Ongoing toxic manifestations of previous treatments (Grade 2 or greater according to
             NCI-CTCAE v4.02) with the exception of alopecia or certain Grade 2 toxicities, which
             in the opinion of the investigator and Sponsor should not exclude the patient - these
             should be discussed on a case by case basis.

          3. Symptomatic brain metastases (patients must be stable for >3 months post RT
             treatment) or spinal cord compression.

          4. Significant baseline hypotension (<90mmgHg systolic or <50 mmHg diastolic).

          5. Uncontrolled hypertension (>160mmHg/100mmHg).

          6. Ability to become pregnant (or already pregnant or lactating). However, those female
             patients who have a negative serum or urine pregnancy test before enrolment and agree
             to use two highly effective forms of contraception (oral, injected or implanted
             hormonal contraception and condom, have a intra-uterine device and condom, diaphragm
             with spermicidal gel and condom) for four weeks before entering the trial, during the
             trial and for six months afterwards are considered eligible.

          7. Male patients with partners of child-bearing potential (unless they agree to take
             measures not to father children by using one form of highly effective contraception
             [condom plus spermicide] during the trial and for six months afterwards). Men with
             pregnant or lactating partners should be advised to use barrier method contraception
             (e.g. condom plus spermicidal gel) to prevent exposure to the foetus or neonate.

          8. Patients must have recovered from effects or major surgery, no major surgery within 4
             weeks prior to the patient receiving Cycle 1 Day 7 (for dose escalation) or C1 Day1
             (for dose expansion). If minor surgery has been performed within 2 weeks of the start
             of trial treatment then the sponsor and CI should be notified of the nature of this
             and agree to patient inclusion.

          9. Co-existing active infection or serious concurrent medical condition.

         10. Known to be serologically positive for Hepatitis B, Hepatitis C or Human
             Immunodeficiency Virus (HIV) (mandatory testing not required).

         11. History of allergy or auto-immune disease.

         12. Significant cardiovascular disease as defined by:

               1. History of congestive heart failure requiring therapy

               2. History of unstable angina pectoris or myocardial infarction up to 6 months
                  prior to trial entry

               3. Presence of severe valvular heart disease

               4. Presence of a ventricular arrhythmia requiring treatment

         13. Concurrent hypotension defined as baseline supine blood pressure systolic <90 mmHg.

         14. Past history of corneal ulceration, dry eye syndrome, glaucoma. Contact lenses should
             also be avoided during participation in the trial.

         15. Any other condition which in the Investigator's opinion would not make the patient a
             good candidate for the clinical trial.

         16. Participation in any other clinical study within the 4 weeks previous to start of
             trial treatment.