Inclusion Criteria

          1. Patient must consent to the study and provide a signed and dated written informed
             consent document prior to any study-specific procedures, sampling, or analyses.

          2. Age ≥18 years

          3. Weight ≥77 lbs (35 kg)

          4. Availability of an archival tumor tissue sample. If archival tumor tissue is not
             available, then tissue from a fresh biopsy can be used.

          5. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1 w/ no clinical
             deterioration over the prior 2 weeks (wks) and likely able to complete at least 9 wks
             of treatment.

          6. Normotensive or well controlled blood pressure (systolic <150 and diastolic <90) w/ or
             without current anti-hypertensive treatment. If there is a diagnosis or history of
             hypertension, patient must have adequately controlled BP on antihypertensive
             medications as demonstrated by 2 BP measurements taken in the clinical setting by a
             medical professional within 1 week (wk) prior to enrollment. Patients on
             anti-hypertensive medication must be willing and able to check and record twice daily
             BP readings for a minimum of 3 wks.

          7. Females should be using adequate contraceptive measures from the time of screening
             until 3 months after study discontinuation, should not be breast feeding and must have
             negative pregnancy test prior to the start of dosing, or must have evidence of
             non-child-bearing potential by fulfilling one of the following criteria at screening:

               -  Post-menopausal: defined as aged more than 50 years and amenorrheic for at least
                  12 months following cessation of all exogenous hormonal treatments.

               -  Documentation of irreversible surgical sterilization by hysterectomy, bilateral
                  oophorectomy, or bilateral salpingectomy, but not tubal ligation.

               -  Women under 50 years-of-age will be considered postmenopausal if they have been
                  amenorrheic for at least 12 months following the cessation of exogenous hormonal
                  treatments, and have serum follicle-stimulating hormone and luteinizing hormone
                  levels in the postmenopausal range for the institution.

          8. Male patients should be willing to use barrier contraception for the duration of the
             study and for 3 months after treatment discontinuation.

          9. Ability to swallow and retain oral medication.

        Additional Inclusion Criteria for Phase 1a Arms AA and EA

        1. Patients in Arms AA and EA must have metastatic prostate cancer w/ histological or
        cytological confirmation. Note: Patient may have bone only metastatic disease.

          -  Patients must be castrate-resistant (i.e. developed progression of metastases
             following surgical castration or during medical androgen ablation therapy). (Patients
             receiving medical castration therapy w/ gonadotropin-releasing hormone analogues
             should continue this treatment during this study.)

          -  Patients must have received prior treatment w/ at least one of the hormonal agents
             (abiraterone acetate, enzalutamide or apalutamide). Patients who received prior
             apalutamide will be allocated to abiraterone acetate (Arm AA). Note: Prior
             chemotherapy is allowed but not required.

          -  Patients must have evidence of disease progression.

        Additional Inclusion Criteria for Phase 1a Arm CA

          1. Patients in Arm CA must have a histologically/cytologically confirmed advanced solid
             tumor malignancy that has received and progressed on standard-of-care therapy(ies).

        Additional Inclusion Criteria for Phase 1a Arms CB and CC

          1. Patients in Arms CB and CC may have metastatic prostate cancer w/ histological or
             cytological confirmation:

             • Patient must be castrate-resistant (i.e., developed progression of metastases
             following surgical castration or during medical androgen ablation therapy). Patients
             receiving medical castration therapy with gonadotropin-releasing hormone analogues
             should continue this treatment during this study. Note: Patient with prostate cancer
             may have bone-only metastatic disease.

             • Patient must have-evidence of disease progression. Or

             • Patients in Cohort CB must have a histologically/cytologically confirmed advanced
             solid tumor malignancy that has received and progressed on standard-of-care
             therapy(ies).

             Or • Patients in Cohort CC should have a histologically/cytologically confirmed
             advanced solid tumor malignancy suitable for treatment with docetaxel.

             Additional Inclusion Criteria for Phase 1b

          1. Patients must have disease that is suitable for repeated measurement, either: a) at
             least one lesion that can be accurately assessed at baseline by computed tomography
             (CT), magnetic resonance imaging (MRI) or X-ray, that is suitable for repeated
             measurement (RECIST v1.1), or b) for patients with mCRPC (Arms I and J), patients must
             have measurable PSA above normal limits (per local ranges).

          2. A minimum of 10 patients with mCRPC, CRC and 'Other' tumors will be required to have a
             site of disease that is safely accessible for biopsy (paired) upon enrollment.
             Accessible lesions are defined as those which are biopsiable (at screening) and
             amenable to repeat biopsy (after 2 wks of monotherapy), unless clinically
             contraindicated. In the case that the second sample is not taken, the patient will
             remain in the study and there will be no penalty or loss of benefit to the patient and
             they will not be excluded from other aspects of the study. The tumor-specific cohorts
             will be closely monitored to ensure the desired number of biopsiable patients are
             enrolled. The requirement for biopsies must be made clear to each patient at the time
             of initial approach by the Investigator.

          3. For post immunotherapy patients with NSCLC (Arms F and G) all of the following must
             apply:

               -  Patients must have advanced or metastatic NSCLC w/ histological or cytological
                  confirmation. Patients with known EGFR-activating mutations or ALK rearrangements
                  are excluded.

               -  Patient must have previously received one (but no more than one) line of previous
                  therapy w/ an anti-PD-1/PD-L1 mAb therapy either alone or in combination and have
                  either progressed or responded and then stopped responding.

          4. For other post-immunotherapy patients (Arm H) all of the following must apply:

               -  Patients must have an immune checkpoint resistant malignancy (for example, RCC,
                  head and neck carcinoma, or MSI high cancers which have approved settings for
                  anti-PD1 treatment), confirmed histologically or cytologically.

               -  Patients must have previously received at least one line (and not more than 2
                  lines) of previous therapy w/ an anti-PD-1/PD-L1 mAb therapy, either alone or in
                  combination and have either progressed or responded and then stopped responding.

          5. For immune checkpoint naïve CRPC patients (Arms I and J) all of the following must
             apply:

             • Patients must have metastatic prostate cancer w/ histological or cytological
             confirmation.

               -  Patients must be castrate-resistant (i.e., developed progression of metastases
                  following surgical castration or during medical androgen ablation therapy).
                  Patients receiving medical castration therapy w/ gonadotropin-releasing hormone
                  analog should continue this treatment during this study.

               -  Patients must have previously received and progressed on standard-of-care
                  therapy(ies).

               -  Approximately 60 out of 80 patients w/ mCRPC enrolled must have measurable
                  disease (approximately 30 out of 40 patients in each of the mCRPC arms I and J)
                  that is suitable for repeated measurement (RECIST v1.1). Enrollment will be
                  monitored to ensure the required number of patients with measurable disease enter
                  the study.

          6. For immune checkpoint naïve patients (Arms K and KD) all of the following must apply:

               -  Patients must have immune checkpoint naïve histologically/cytologically confirmed
                  advanced or metastatic colorectal carcinoma (CRC).

               -  Patients must have previously received and progressed on at least 1 prior
                  chemotherapy regimen.

          7. For other immune checkpoint naïve tumor patients (Arm L) all of the following must
             apply:

               -  Patients w/ other immune checkpoint naïve histologically/ cytologically confirmed
                  advanced solid tumor type that has received and progressed on standard-of-care
                  therapy(ies).

        Exclusion Criteria

          1. Treatment with any of the following:

               -  Nitrosourea or mitomycin C within 6 wks of the first dose.

               -  Any systemic anti-cancer chemotherapy, small molecule, biologic, or hormonal
                  agent from a previous treatment regimen or clinical study within 21 days or 5
                  half-lives (whichever is shorter). At least 7 days must have elapsed between the
                  last dose of such agent and the first dose of study drug. EXCEPTION:
                  Androgen-deprivation therapy is recommended for patients w/ prostate cancer.

               -  Enrollment into another therapeutic clinical trial. EXCEPTION: Patients are
                  allowed to participate in investigational imaging or non-therapeutic studies.

               -  Patient has had Rx or non-Rx drugs or other products known to be sensitive BCRP
                  or OAT1 substrates or to be potent inhibitors/inducers of CYP1A2, which cannot be
                  discontinued 2 wks prior to Day 1 of dosing and withheld throughout the study
                  until 2 wks after the last dose of AZD4635.

               -  Herbal preparations/medications are not allowed throughout the study, including
                  but not limited to St. John's Wort, kava, ephedra (ma huang), gingko biloba,
                  dehydroepiandrosterone, yohimbe, saw palmetto, and ginseng. Patients should stop
                  using these herbal medications 7 days prior to the first dose of AZD4635.

               -  Patient may not be assigned to abiraterone acetate arm (Arm AA) if
                  co-administration of a strong CYP3A4 or a CYP2D6 substrate with a narrow
                  therapeutic index is required during study treatment.

               -  Patient may not be assigned to an enzalutamide arm (Arm EA) if co-administration
                  of strong CYP2C8 inhibitor, strong or moderate CYP3A4 or CYP2C8 inducer, or
                  CYP3A4, CYP2C9, and CYP2C19 substrates with a narrow therapeutic index is
                  required during study treatment.

               -  Ongoing treatment w/ Coumadin.

               -  Concomitant medications w/ another A1R antagonist that would increase risk of
                  seizure (e.g., theophylline or aminophylline).

               -  AZD4635 in the present study (i.e., dosing w/ AZD4635 previously initiated in a
                  different arm in this study), or prior therapy w/ AZD4635 or any other A2AR
                  antagonist.

               -  Ongoing corticosteroid use. NOTE: mCRPC patients assigned to an arm with
                  abiraterone acetate (Arm AA) should take prednisone as prescribed for
                  glucocorticoid replacement therapy and patients assigned to the docetaxel arm
                  (Arm CC) should take prophylactic dexamethasone (or equivalent) to prevent severe
                  hypersensitivity reactions.

               -  Major surgery (excluding placement of vascular access) within 4 wks of the first
                  dose of study treatment.

               -  Radiotherapy w/ a wide field of radiation within 4 wks or radiotherapy w/ a
                  limited field of radiation for palliation within 2 wks of the first dose of study
                  treatment.

          2. Patient w/ prior history of myocardial infarction, transient ischemic attack, or
             stroke within 3 months prior to the scheduled first dose of oleclumab treatment (Arm
             CB).

          3. With the exception of alopecia, any unresolved toxicities from prior therapy greater
             than CTCAE Grade 1 at the time of starting study treatment must be discussed with the
             Medical Monitor.

          4. History of seizures, central nervous system tumors or CNS metastasis. Due to the
             incidence of silent CNS metastases in patients with advanced NSCLC, such patients must
             undergo mandatory screening with brain MRI or CT scan to determine eligibility.

          5. Significant mental illness in the 4-wk period preceding drug administration.

          6. As judged by the investigator, any evidence of severe or uncontrolled systemic
             disease, including uncontrolled hypertension, active bleeding diatheses, or active
             infection, including hepatitis B, hepatitis C, and human immunodeficiency virus.
             Screening for chronic conditions is not required.

          7. History or presence of another primary invasive malignancy except for:

             • Malignancy treated w/ curative intent and w/ no known active disease ≥2 years before
             the first dose of study drug and of low potential risk for recurrence.

             • Adequately treated non-melanoma skin cancer or lentigo maligna without evidence of
             disease.

             • Adequately treated carcinoma in situ without evidence of disease.

             • Localized non-invasive primary under surveillance.

          8. Any of the following cardiac criteria:

             • Mean resting corrected QT interval (QTcF) >470 msec obtained from 3 ECGs.

             • Any clinically important abnormalities in rhythm, conduction, or morphology of
             resting ECGs, e.g., complete left bundle branch block, third degree heart block.

               -  Any factors that increase the risk of QTc prolongation or risk of arrhythmic
                  events such as heart failure, hypokalemia, congenital long QT syndrome, family
                  history of long QT syndrome or unexplained sudden death under 40 years-of-age, or
                  any concomitant medication known to prolong the QT interval. Patients receiving a
                  medication(s) known to prolong QT internval may be discussed w/ the Medical
                  Monitor or Sponsor for study approval.

               -  Ejection fraction <55% or less than the lower limit of normal of the
                  institutional standard.

          9. Inadequate bone marrow reserve or organ function as demonstrated by any of the
             following laboratory values:

             • Absolute neutrophil count <1.5 x 10^9/L

               -  Platelet count <100 x 10^9/L

               -  Hemoglobin <90 g/L

               -  ALT and/or AST >2.5 x the upper limit of normal (ULN) if no demonstrable liver
                  metastases or >5 x ULN in the presence of liver metastases

               -  Total bilirubin >1.5 x ULN

               -  Creatinine >1.5 x ULN concurrent with creatinine clearance <50 mL/min

         10. Refractory nausea and vomiting, chronic gastrointestinal diseases, or previous
             significant bowel resection that would preclude adequate absorption of AZD4635.

         11. Any patient w/ open oral ulceration(s) should avoid dosing with AZD4635 oral
             suspension.

         12. Patients w/ severe hepatic impairment (Child-Pugh Class C) are not permitted to enroll
             in the mCRPC plus hormone arms containing abiraterone acetate.

         13. Organ transplant that requires the use of immunosuppressive treatment.

         14. Active or prior documented autoimmune or inflammatory disorders (including
             inflammatory bowel disease [e.g. colitis, Crohn's disease], diverticulitis, celiac
             disease, systemic lupus erythematous, Wegner's syndrome, myasthenia gravis, Grave's
             disease, rheumatoid arthritis, hypophysitis, uveitis, autoimmune pneumonitis,
             autoimmune nephritis or nephropathy, etc.) within the past 3 years prior to the start
             of treatment. The following are exceptions to this criterion:

               -  Vitiligo or alopecia.

               -  Hypothyroidism (e.g., following Hashimoto's disease) stable on hormone
                  replacement.

               -  Psoriasis or eczema not requiring systemic treatment.

         15. Patients w/ prior ≥Grade 3, serious, or life threatening immune-mediated reactions
             following prior anti-PD-1 or other immune-oncology therapies.

         16. History of hypersensitivity to AZD4635 or drugs w/ a similar chemical structure or
             class to AZD4635.

         17. Judgment by the Investigator or the Medical Monitor that the patient should not
             participate in the study if the patient is unlikely to comply w/ study procedures,
             restrictions, and/or requirements.