A Study of RNK08954 in Subjects With Advanced Solid Tumors With KRAS ((Kirsten Rat Sarcoma) G12D Mutation

Inclusion Criteria:

1. Must be 18 years of age or older.

2. Must have pathologically documented locally advanced or metastatic malignancyharboring KRAS G12D mutations identified through deoxyribonucleic acid (DNA)sequencing of tumor tissues or circulating deoxyribonucleic acid (ctDNA) performedlocally.

3. Must have received prior standard therapy appropriate for their tumor type, or inthe opinion of the investigator, would be unlikely to derive further clinicallymeaningful benefit from appropriate standard of care therapy.

4. Must have measurable lesion(s) per Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1 by Computed tomography (CT) scan with contrast (magneticresonance imaging (MRI), if the patient is allergic to contrast media).

• Measurable disease may be in the field of prior irradiation; however, at least 3 weeks must have elapsed between the completion of radiation therapy and thebaseline scan documenting disease status.

• Bone disease is considered radiologically measurable only if there is at leasta 50% lytic component. NOTE: Bone disease consisting of only blastic lesion is not considered measurable. NOTE: in Phase 1a, patients must have measurable or evaluable disease.

5. Archival or fresh tumor tissue must be available for evaluating relevant biomarkers.Formalin-fixed paraffin-embedded (FFPE)block preferred, or a minimum of 3 unstainedFFPE slides of one archived block is required. NOTE: cytology samples from fine needle aspirates or brushing biopsies are notsufficient. NOTE: Phase 1a and 1b: Patients are additionally encouraged to undergo pre-treatmenttumor biopsy.

6. Must have adequate performance status, Appendix D. o Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) score of 0, or

8. Must be able to take oral medications and willing to record daily adherence to theinvestigational product.

9. Must have adequate laboratory parameters at baseline:

• Absolute neutrophil count ≥ 1.2 x 109/L.

• Hemoglobin greater than or equal to (≥) 9 g/dL.

• Platelet count ≥ 75 x 109/L.

• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) less thanor equal to (≤) 2.5 x upper limit of normal (ULN) (≤ 5 x ULN in presence ofliver metastases).

• Total bilirubin ≤ 1.5 x institutional ULN [less than (<) 2.5 x ULN for patientswith documented Gilbert's syndrome or < 3.0 x ULN for patients for whom theindirect bilirubin level suggests an extrahepatic source of elevation].

• Calculated creatinine clearance greater than (>) 60 mL/min. Actual body weightshould be used for calculating creatinine clearance (e.g. using theCockcroft-Gault formula). For patients with a Body Mass Index (BMI) > 30 Kg/m2, lean body weight should beused instead.

• Acceptable coagulation parameters: Fibrinogen ≥ 1.5 g/dL, or partialthromboplastin time (PTT) ≤ 1.5 X institutional ULN, or internationalnormalized ratio (INR) < 1.5 X institutional ULN or within target range if apatient is on prophylactic anti-coagulant therapy.

• Serum albumin ≥ 3.0 g/dL.

9. Must have life expectancy of > 12 weeks according to the Investigator's clinicaljudgment.

10. Females of childbearing potential must have a negative pregnancy test at screeningand additional pregnancy test prior to first dose. NOTE: Positive pregnancy test may occur in approximately 10% of cancer patients, whoare otherwise postmenopausal. This is due to Human Chorionic Gonadotrophin (HCG)secreted by some tumor types such as ovarian or colorectal cancer (CRC), even inpostmenopausal women. A quantitative test should be performed in patients with apositive serum pregnancy test, otherwise thought to be postmenopausal.

11. Males and females of childbearing potential must agree to use a highly effectivemethod of contraception during treatment and for at least 6 months after the lastdose of study treatment. These include, but not limited to: o Combined (estrogen and progestogen containing) hormonal contraception associatedwith inhibition of ovulation (i.e. intravaginal or transdermal).

• Progestogen-only hormonal contraception associated with inhibition of ovulation (i.e. injectable or implantable).

• Intrauterine device.

• Bilateral tubal occlusion.

• Vasectomized partner.

• Sexual abstinence (defined as refraining from heterosexual intercourse duringthe entire period of risk associated with the study treatments) is intended.The true abstinence is when this is in line with the preferred and usuallifestyle of the patient. (Periodic abstinence [e.g. calendar, ovulation,symptom-thermal, post-ovulation methods] and withdrawal are not acceptablemethods of contraception). NOTE: A patient is not considered in childbearing potential if any of the followingcriteria is met:

• has had a hysterectomy, bilateral salpingectomy, or bilateral oophorectomy.

• Age ≥ to 60 years and is amenorrhoeic.

• Age < 60 years and has been amenorrhoeic for ≥12 months (including no irregularmenses or spotting) in the absence of any medication which induces a menopausalstate and has ovarian failure as indicated by serum estradiol andfollicle-stimulating hormone levels. NOTE: Male patients will be advised to arrange for the freezing of sperm samplesprior to the start of the study, and not to donate sperm until 6 months afterdiscontinuation of study treatment.

12. Must be able to understand and comply with the conditions of the protocol and musthave read and understood the consent form and provided written informed consent. Food Effect Assessment- Specific Inclusion Criteria

13. Must be able to eat a standardized high-fat, high-caloric meal within 30 minutes.

14. Must be able to fast for a minimum of 10 hours. Phase 1b and Phase 2 Specificinclusion criteria

15. Patient must have received at least one but no more than two prior lines of systemiccytotoxic chemotherapy in locally advanced or metastatic setting.

16. The status of KRAS G12D mutations will be performed in a central laboratory chosenby the Sponsor.

Exclusion Criteria:

A patient is not eligible to participate in the study if any of the following criteria are met:

1. Concurrent anticancer therapy [chemotherapy, monoclonal antibodies, targetedtherapy, hormonal therapy or investigational agents] within the lesser of 28 days or 5 half-lives before study Day 1. NOTE: Patient must agree not to participate in any other interventional clinicalstudies during their participation in this trial while on study treatment. NOTE: patients receiving hormonal ablation therapy for breast cancer or hormonerefractory prostate cancer are allowed. NOTE: Patients taking part in surveys or observational studies are eligible toparticipate in this study.

2. Significant acute decline in clinical status including:

-Decline in ECOG PS to >1 between baseline visit and within 72 hours prior tostarting study treatment.

-Weight loss of ≥10% during screening.

3. Presence of active or symptomatic untreated central nervous system (CNS) metastases. NOTE: Patients with asymptomatic or stable CNS metastases are eligible, providedthat the CNS metastases are radiologically and clinically stable for at least 2weeks prior to enrollment, or on a stable or decreasing dose of ≤ 10 mg dailyprednisone (or equivalent).

4. Unresolved toxicities from prior anticancer therapy, defined as not having resolvedaccording to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0Grade ≤ 1, or to levels dictated in the eligibility criteria, with the exception ofalopecia. NOTE: Grade 2 or 3 toxicities from prior anticancer therapy that are consideredirreversible (present and stable for >6 months) may be allowed if they are nototherwise described in the exclusion criteria and after a consultation between theMedical Monitor and the Investigator.

5. Prior radiotherapy to the only area of measurable disease, unless there isdocumented disease progression. NOTE: Patients must have completed treatment and recovered from all acutetreatment-related toxicities prior to administration of the first dose of RNK08954.

6. Presence of gastrointestinal (GI) tract disease causing inability to take oralmedication, such as malabsorption syndrome, requirement for intravenousalimentation, uncontrolled inflammatory GI disease, e.g. Crohn's disease orulcerative colitis, or any other severe acute or chronic condition that may increasethe risk of study participation including, e.g. history of abdominal fistula, GIperforation, peptic ulcer.

7. Current or history within 6 months prior to study enrollment of medicallysignificant cardiovascular disease including symptomatic congestive heart failure >New York Heart Association (NYHA) Class II, unstable angina pectoris, clinicallysignificant cardiac arrhythmia, or a history of long QT Syndrome (the heart'selectrical activity as graphed on an electrocardiogram) or a family member with thiscondition. NOTE: patients with a marked baseline prolongation of QT/QTc (corrected) interval (e.g. repeated demonstration of a corrected QT (QTc) interval ≥ 470 mSec (onethousandth of a second) will be excluded. A consistent method of QTc calculationmust be used for each patient's QTc measurements. QTcF (Fridericia's formula) ispreferred.

8. Use of concomitant medications that have the potential to cause clinically relevantdrug-drug interactions with RNK08954; including but not limited to:

• All herbal medicines (e.g. St John's wort).

• Use of strong inhibitors of Polymeric P-glycoprotein) P-gp within two weeksprior to Study Day 1.

• Use of strong inducers or inhibitors of Cytochrome P450 3A4 (CYP3A4) within twoweeks prior to Study Day 1.

• Use of known 3A4, or C member 19 (2C19) sensitive substrates (with a narrowtherapeutic window) within two weeks prior to Study Day 1. NOTE: other supplemental medicines, vitamins received by the patients within 3 weeksof the study enrollment will be reviewed and acknowledged or approved by theInvestigator and the Sponsor Medical Monitor.

9. Pregnancy or breast-feeding or planning to breast feed during the study or within 6months after study treatment.

10. Untreated human immunodeficiency virus (HIV). NOTE: Patients with a known history ofHIV infection should have a cluster of differentiation 4 (CD4)+ thymus (T)-cell (CD4+) count ≥ 350 cells/mL to be eligible.

11. Active infection requiring systemic antibiotics, antiviral or antifungal treatment. NOTE: Patient must be medically stable, afebrile, and not taking antimicrobialtreatment for ≤ 3 days prior to the first dose of study drug.

12. Known hepatitis B virus, or Hepatitis C virus:

• Positive Hepatitis B Surface Antigen (Hep B sAg) (indicative of chronicHepatitis B), positive Hepatitis total core antibody with negative Hep B sAg (suggestive of occult hepatitis B).

• Detectable Hepatitis C virus (HCV) Ribonucleic acid (RNA) by Polymerase chainreaction (PCR) (indicative of active Hepatitis C), or positive Hepatitis CAntibody (Hep C Ab). NOTE: testing at screening is not required unless clinically indicated by theInvestigator. NOTE: Patients with a history of hepatitis B or C are allowed if hepatitis B virus (HBV )DNA or hepatitis C virus (HCV) RNA are undetectable.

13. Known hypersensitivity to any of the components of the study drug.

14. Other conditions, psychiatric illness/social situations or any other seriousuncontrolled medical disorders in the opinion of the Investigator that would limitcompliance with study requirements.

Phase 1b and Phase 2 Specific exclusion criteria 15. History of other malignancies except adequately treated non-melanoma skin cancer, curatively treated in-situ cancer of the cervix, or other solid tumors curatively treated by surgery alone or surgery plus radiotherapy with no evidence of disease for >2 years.

16. Prior treatment with KRAS G12D or Pan KRAS inhibitor.