A Study of BPI-1178 in Patients With Advanced Solid Tumor and HR+/HER2- Breast Cancer

Inclusion Criteria:

1. Have given written informed consent prior to any study specific procedures.

2. Male or female, aged ≥18 years.

3. Subjects with advanced solid tumors:

• Phase 1: Histologically or cytologically confirmed, locally advanced (notamenable to curative treatment of surgical resection or radiation therapy),recurrent, or metastatic solid tumors that were refractory to standard therapyor for which no standard-of-care therapy.

• Phase 2a Cohort A: HR+/HER2- locally advanced, recurrent, or metastatic breastcancer with disease progression after first-line endocrine therapy (notfulvestrant) or intolerant of it, histologically confirmed by the primaryand/or metastatic lesions, not amenable to chemotherapy or curative treatmentof surgical resection or radiation therapy; if the pathology of the primary andmetastatic lesions are inconsistent, diagnosis should be based on metastaticlesions' pathology.

• Phase 2a Cohort B: HR+/HER2- locally advanced, recurrent, or metastatic breastcancer with no prior systemic therapy in this disease setting or relapse morethan 1 years from completion of adjuvant endocrine therapy, histologicallyconfirmed by the primary and/or metastatic lesions, not amenable tochemotherapy or curative treatment of surgical resection or radiation therapy;if the pathology of the primary and metastatic lesions are inconsistent,diagnosis should be based on metastatic lesions' pathology.

• Female patients with breast cancer at Phase IIa must also meet the followingcriteria: (1) Postmenopausal patients must meet at least one of the following criteria:

1. Age ≥ 60 years old;

2. Patients < 60 years of age who have menstruation ceased for at least 12consecutive months and have not received chemotherapy, tamoxifen,toremifene or ovarian function inhibitors, and have blood estrogen and FSHlevels within the reference range for postmenopausal women;

3. Previous bilateral ovariectomy;

4. Patients < 60 years of age who are being treated with tamoxifen ortoremifene with blood estrogen and FSH levels within the reference rangefor postmenopausal women. (2) Premenopausal/perimenopausal patients must meet the following criteria:Premenopausal/perimenopausal patients requiring ovarian function suppressionmust start treatment at least 4 weeks prior to enrollment and the treatmentshould be maintained during the trial.

5. At least 1 measurable lesion based on the RECIST v1.1 criteria.

6. Life expectancy≥ 12 weeks.

7. Eastern Cooperative Oncology Group (ECOG) Performance Status (PS)≤1.

8. Adequate bone marrow and organ function, defined as following:

9. absolute neutrophil count≥1.5×10^9/L, platelets≥100×10^9/L, hemoglobin≥100 g/L;

10. total bilirubin≤1.5×ULN(≤3×ULN for Gilbert syndrome), alanine aminotransferaseand aspartate aminotransferase≤3×ULN;

11. serum creatinine≤1.5×ULN or a creatinine clearance calculated byCockcroft-Gault formula≥50 mL/min; urinary protein measured bysemi-quantitative method<2+; if urinary protein measured by semi-quantitativemethod at baseline ≥2+, 24-h urinary protein<1g;

12. activated partial thromboplastin time and international normalizedratio≤1.5×ULN;

13. LVEF≥50%;

14. Corrected QT interval (QTcF)<450ms for men and <470ms for women at resting.

15. Female subjects should take effective contraceptive methods during the study and for 60 days after the last dose of BPI-1178, and must have a negative pregnancy testprior to dosing if of child-bearing potential, or must have evidence ofnon-child-bearing potential; male subjects should take effective contraceptivemethods during the study and for 120 days after the last dose of BPI-1178.

16. All subjects must have enough mental behavior ability, understand the nature andsignificance of the study, as well as the risks associated with the study.

Exclusion Criteria:

1. Currently receiving or have received any CDK4/6 inhibitors.

2. Have had allergies or history of severe allergies.

3. Have participated in any clinical trials within 4 weeks prior to the dosing ofBPI-1178.

4. Have received anti-tumor therapy (including chemotherapy, endocrine therapy,targeted therapy, immunotherapy, tumor embolization, etc.; have receivedradiotherapy within 2 weeks before taking the investigational product) within 4weeks before starting to take the investigational product <except forpremenopausal/perimenopausal patients with Gonadotropin-releasing hormone analogues [GnRHa] therapy allowed in Phase IIa study>.

5. Other malignancies present or previously present at the time of enrollment or stillunder treatment at the time of enrollment (only applicable to Phase IIa study)

6. Any toxicity related to previous treatment before enrollment defined by CTCAE (v5.0)Grade≥2 (except hair loss).

7. Presence of third interstitial fluid that cannot be controlled by drainage or othermethods (such as large amounts of pleural fluid and ascites).

8. Requiring long-term treatment of steroid.

9. Having uncorrectable hypokalemia and hypomagnesemia at enrollment.

10. Meet any of the following criteria: Various clinically significant heart rhythm andconduction abnormalities, such as atrial fibrillation, complete left bundle branchblock, Level III conduction block, Level II conduction block, and PR interval > 250msec; Various factors that might increase risks of QT increased or arrhythmiaevents, e.g., symptomatic cardiac failure - New York Heart Association (NYHA) class 2-4, long QT syndrome congenital, Brugada syndrome, previous histories of QTincreased (> 470 ms for males, > 480 ms for females) or TdP attack, first degreerelative of the family with long QT syndrome or sudden death before 40 years' oldwith unexplained cause, and concomitant medication which may prolong QT interval;Suffering from following diseases within 6 months prior to administration ofinvestigational product, including unstable angina pectoris, myocardial infarction,coronary heart disease, cerebrovascular accident or pulmonary embolism, or acceptingcardiac revascularization.

11. Known active infection, such as hepatitis B (HBV DNA ≥ 200 IU/mL), hepatitis C,human immunodeficiency virus (HIV) infection.

12. Have a history of allogeneic organ transplantation and allogeneic hematopoietic stemcell transplantation.

13. Based on the judgement of investigators, there might be multiple factors which couldimpact taking and absorption of BPI-1178, including gastrointestinal factors (e.g.,obviously uncontrollable inflammatory gastrointestinal disorder, abdominal colostomywithin 6 months or previous history of gastrointestinal perforation, extensiveresection of small intestine and requirement of tube feeding or water/ nutritionalsupplement by parenteral route, inability to swallow, chronic diarrhoea andintestinal obstruction, etc.)

14. Have spinal cord compression, metastases of the meninges, or brain metastases withobvious symptoms. The following cases of brain metastases without symptoms can beenrolled: brain metastases without obvious symptoms diagnosed at screening visit,steroids and/or local treatment not required judged by investigator; brainmetastases without obvious symptoms after local treatment (such as radiotherapy),and steroids and/or antiepileptic therapy has stopped for at least 7 days before thefirst dosing of BPI-1178.

15. In the judgment of the investigator, have a concomitant disease (such as severehypertension, diabetes, thyroid disease, severe infection, portal hypertension,cirrhosis, etc.) that would endanger the subjects' safety or affect the completionof the study.

16. Have had major surgery (craniotomy, thoracotomy, or laparotomy) or unhealed wounds,ulcers, or fractures within 4 weeks prior to the dosing of BPI-1178.

17. Pregnant or lactating women, or fertile women with pregnancy test positive atbaseline.

18. Any factors that may endanger subject's safety and may affect subject's compliancewith the study.

19. Drug abuse, alcoholic addiction, medical and mental illness and social barriersjudged by investigator, which may interfere the subjects' participation in the studyor affect the evaluation of study endpoints . Any factor that investigator believesmay make the subjects not suitable to receive BPI-1178. Subjects are unwilling orunable to comply with the requirements of the study protocol.