A Study of YL202 in Patients With Locally Advanced or Metastatic Non-small Cell Lung Cancer and Breast Cancer

This is a phase 1, multicenter, open-label, first-in-human study of YL202 conducted in the United States and China.The study will evaluate the safety and tolerability of YL202 in patients with locally advanced or metastatic epidermal growth factor receptor (EGFR)-mutated NSCLC or hormone receptor (HR)-positive and HER2-negative BC, which have been heavily treated by standard treatment.

Inclusion Criteria:Informed of the trial before the start of the trial and voluntarily sign their name and date on the informed consent formAged ≥18 yearsEastern Cooperative Oncology Group performance status (ECOG PS) of 0 to 2Adequate organ and bone marrow functionFemale patients of childbearing potential must agree to use a highly effective form of contraception and not donate, or retrieve for their own use, ova from the time of screening and throughout the study period, and for at least 6 months after the last dose of study drug. Male patients must agree to use a highly effective form of contraception and not freeze or donate sperm from the time of screening and throughout the study period, and for at least 6 months after the last dose of study drug.Life expectancy of ≥3 monthsAble and willing to comply with protocol visits and proceduresFor NSCLC patients:Have a histologically or cytologically confirmed diagnosis of locally advanced or metastatic NSCLC not amenable to curative surgery or radiationHave a documentation of an EGFR-activating mutation (exon 19 deletion or L858R) detected at diagnosis or thereafterHave documentation of disease progression on or after, or are intolerant to prior standard treatment regimens for locally advanced or metastatic disease.For BC patients:Have a histologically or cytologically confirmed diagnosis of unresectable locally advanced or metastatic HR-positive and HER2-negative BC (per American Society of Clinical Oncology-College of American Pathologists [ASCO-CAP] guidelines)Have documentation of disease progression on or after, or are intolerant to prior standard treatment regimens for locally advanced or metastatic disease.Have at least 1 measurable tumor lesion according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1Exclusion Criteria:Intolerant to prior treatment with a topoisomerase I inhibitor or an ADC that consists of a topoisomerase I inhibitor, including but not limited to topotecan, irinotecan, and DXd (e.g., severe diarrhea)Concurrent enrollment in another clinical study, unless it is an observational (non-interventional) clinical study or during the follow-up period of an interventional studyInadequate washout period for prior anticancer treatment before the first dose of study drugUndergone major surgery (not including diagnostic surgery) within 4 weeks before the first dose of study drug or expect major surgery during the studyPrior allogeneic bone marrow transplantation or solid-organ transplantationReceived systemic steroids (>10 mg/day of prednisone or its equivalent) or other immunosuppressive therapy within 2 weeks before the first dose of study drug. The following are exceptions to this criterion:Intranasal, inhaled, topical steroids, or local steroid injections (e.g., intra articular injection)Systemic steroids at physiological doses as replacement therapy (e.g., physiological corticosteroid replacement therapy for adrenal or pituitary insufficiency)Steroids as premedication for hypersensitivity reactions (e.g., computed tomography [CT] scan premedication)Received any live vaccine within 4 weeks before the first dose of study drug or intend to receive a live vaccine during the studyA history of leptomeningeal carcinomatosisBrain metastases or spinal cord compression unless asymptomatic or treated and stable off steroids and anti-convulsants for at least 2 weeks before the first dose of study drugUncontrolled or clinically significant cardiovascular disease.A history of (noninfectious) interstitial lung disease (ILD)/pneumonitis that requires steroids, current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at screeningClinically significant concomitant pulmonary disease.Clinically significant corneal diseaseHave a diagnosis of Gilbert's syndromeUncontrolled third-space fluid (e.g., pleural effusions, ascites, pericardial effusions) that requires repeated drainageActive gastric and duodenal ulcers, ulcerative colitis, or other gastrointestinal conditions that may cause bleeding or perforation by the investigator's discretionActive infection that requires systemic therapy within 1 week before the first dose. Patients receiving prophylactic anti-infective therapy (e.g., to prevent a urinary tract infection or chronic obstructive pulmonary disease exacerbation) may be eligible after discussion with the sponsor.Known human immunodeficiency virus (HIV), hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. Patients with HIV, HBV, or HCV infection may be enrolled after evaluation of eligibility based on FDA's guideline Cancer Clinical Trial Eligibility Criteria: Patients with HIV, Hepatitis B Virus, or Hepatitis C Virus InfectionsAny other primary malignancy within 3 years before the first dose of study drug, except adequately resected non-melanoma skin cancer, curatively treated in situ disease, or other curatively treated solid tumorsUnresolved toxicities from previous anticancer therapy, defined as toxicities (other than alopecia and pigmentation) not yet resolved to NCI CTCAE Grade ≤1, baseline, or the level specified in the inclusion/exclusion criteria. Patients with chronic Grade 2 toxicities who are asymptomatic or adequately managed with stable medication may be eligible after discussion with the sponsor.A history of severe hypersensitivity reactions to the drug substances, inactive ingredients in the drug product, or other monoclonal antibodiesWomen who are breastfeeding or pregnant as confirmed by pregnancy tests performed within 3 days before the first doseAny illness, medical condition, organ system dysfunction, or social situation, including but not limited to mental illness or substance/alcohol abuse, deemed by the investigator to be likely to interfere with a patient's ability to sign informed consent, adversely affect the patient's ability to cooperate and participate in the study, or compromise the interpretation of study results.