Sponsor: Sumitomo Pharma America, Inc. (industry)
Phase: 1/2
Start date: Aug. 14, 2024
Planned enrollment: 120
SMP‑3124LP (SMP‑3124) is an investigational, liposome‑encapsulated small‑molecule inhibitor of checkpoint kinase 1 (CHK1) being developed by Sumitomo Pharma for advanced solid tumors. A first‑in‑human, global, multicenter Phase 1/2 trial (dose‑escalation and expansion) began enrolling in August 2024 in the United States and Japan; as of May 2025 it remained recruiting. No human efficacy or safety outcomes have been reported publicly yet. (sumitomo-pharma.com)
Trial: NCT06526819 (SMP‑3124‑101), “SMP‑3124LP in Adults With Advanced Solid Tumors.” Open‑label Phase 1 dose‑escalation/dose‑optimization followed by Phase 2 expansion. Dosing is by continuous IV infusion every 2 weeks (with an option to explore every 3 weeks). Provisional dose levels include 20, 40, 60, 90, and 120 mg/m². Primary objectives include determining the recommended Phase 2 dose via dose‑limiting toxicities and characterizing safety; antitumor activity (e.g., ORR by RECIST v1.1) is a stated outcome. Sites include leading U.S. cancer centers and a site in Japan. (cdek.pharmacy.purdue.edu)
Status: Recruiting (first patient enrollment August 14, 2024; updates processed May 13, 2025). Estimated primary completion December 2028. (cdek.pharmacy.purdue.edu)
Human data: No efficacy results in humans have been posted or published as of October 7, 2025. (cdek.pharmacy.purdue.edu)
Preclinical signal: In patient‑derived xenograft models of ovarian cancer, including platinum‑resistant tumors, SMP‑3124 produced >40% tumor regression from baseline in 7/14 models and complete remissions in 3/14. Additional xenograft and orthotopic models demonstrated antitumor activity and prolonged survival; synergy with gemcitabine was observed preclinically. (aacrjournals.org)
Human data: No safety results in humans have been reported publicly yet. The ongoing first‑in‑human study’s primary objective is safety/tolerability and dose‑limiting toxicities. (cdek.pharmacy.purdue.edu)
Preclinical observations: Multiple xenograft studies reported antitumor activity without severe side effects or weight loss; liposomal delivery is intended to alter pharmacokinetics and reduce systemic toxicity compared with non‑encapsulated CHK1 inhibition. (aacrjournals.org)
Note: Because the clinical study is in early recruitment and no result summaries are posted, conclusions about efficacy and safety in humans cannot yet be drawn.
Last updated: Oct 2025
Goal: Evaluate safety, tolerability, pharmacokinetics, and preliminary antitumor activity of the investigational CHK1 inhibitor SMP-3124LP and establish a recommended Phase 2 dose in adults with advanced solid tumors.
Patients: Adults with histologically or cytologically confirmed advanced, recurrent, or metastatic solid tumors who have progressed on standard therapy and lack alternatives with survival benefit. Tumor types for dose escalation include platinum-resistant ovarian/fallopian tube/primary peritoneal cancer, triple-negative breast cancer, squamous cell carcinoma of the anus, squamous cell carcinoma of the head and neck, non-small cell lung cancer, and recurrent/persistent uterine serous cancer. Dose expansion will enroll separate cohorts for platinum-resistant ovarian cancer, triple-negative breast cancer, and squamous cell carcinoma of the anus. ECOG 0–2, adequate organ function, and resolution of prior therapy toxicities are required. Key exclusions include prior CHK1/CHK2/WEE1/ATR inhibitor exposure, active CNS metastases, significant cardiac disease or QTcF >470 ms, recent major surgery, strong CYP1A2/2D6 inhibitor use, active serious infection, pregnancy/breastfeeding, and specific ovarian cancer exclusions (recent bowel obstruction, platinum-refractory disease).
Design: Global, multicenter, open-label, first-in-human Phase 1/2 study with non-randomized dose escalation/optimization followed by tumor-specific dose expansion. Planned enrollment is approximately 120 participants.
Treatments: SMP-3124LP administered as a continuous intravenous infusion on a q2w schedule during dose escalation with possible q3w schedule per Safety Review Committee, using provisional doses of 20, 40, 60, 90, and 120 mg/m2 with allowance for intermediate levels. In dose expansion, SMP-3124LP is given at the recommended Phase 2 dose determined in Part 1. SMP-3124LP is a liposomally encapsulated CHK1 inhibitor designed to disrupt the DNA damage response in tumor cells with high replication stress, promoting apoptosis. The liposomal formulation aims to enhance exposure and tumor delivery versus non-liposomal CHK1 inhibitors. Preclinical data have shown antitumor activity across xenograft models and synergy with gemcitabine without added hematologic toxicity; no human efficacy results are available yet.
Outcomes: Primary endpoints: determination of dose-limiting toxicities within 28 days to establish the recommended Phase 2 dose; incidence of adverse events and serious adverse events; objective response rate. Secondary endpoints: pharmacokinetics of SMP-3124 and SMP-3124LP (Cmax, AUC); duration of response per RECIST v1.1.
Burden on patient: High. As a first-in-human Phase 1/2 study with continuous IV infusions every 2 or 3 weeks, participants should expect prolonged infusion visits, intensive safety monitoring, and frequent pharmacokinetic blood sampling, particularly in early cycles. Serial imaging for response assessments and potential on-treatment biopsies or expanded labs may be required per protocol and site practice. Travel frequency is higher than standard care early in treatment due to safety reviews and DLT monitoring, with additional constraints on concomitant medications (e.g., CYP1A2/2D6 inhibitors) and contraception requirements for 6 months after last dose.
Last updated: Oct 2025
Inclusion Criteria:
- Histologically or cytologically-confirmed cancer that is advanced, recurrent, or metastatic with the following origins, and whose disease progressed on standard therapy and for whom there are no alternative therapies that may confer overall survival benefit.
For patients in the Dose Escalation part:
1. Platinum-resistant ovarian cancer
* Histologically diagnosed ovarian, fallopian tube, or primary peritoneal cancer, with predominantly high-grade (Grade 2 or 3) epithelial features (serous and clear cell)
* Platinum resistant is defined as relapsed within 6 months after the last dose of platinum-based therapy
2. Triple negative breast cancer - ER- and PR-negative with HER2 negative
* HER2 negative is defined as one of the following: 0 or 1+ by IHC, or if IHC 2+, then in situ hybridization is negative per the ASCO-CAP HER2 guidelines
* ER- and PR-negative is defined as \< 10% of cells expressing hormonal receptors by IHC, as per standard guidelines
3. Squamous cell carcinoma of the anus
- Patient with locally advanced ineligible for surgery is allowed.
4. Squamous cell carcinoma of the head and neck
5. Non-small cell lung cancer (NSCLC: adenocarcinoma, large cell, and squamous cell carcinoma)
6. Uterine serous cancer (recurrent or persistent)
For Patients in the Dose Expansion Part:
7. Cohort A: PROC (same as above)
8. Cohort B: TNBC (same as above)
9. Cohort C: SCCA (same as above)
* ECOG performance \= 2 at screening
* Recovered from any prior treatment related toxicities
* Adequate organ function as evidenced by:
a. Hemoglobin \>/= 9 g/dL (transfusion or use of erythropoietin to obtain this are not permitted) b. Absolute neutrophil count \>/= 1500 uL (platelet transfusion not allowed to achieve this) c. Platelet count \>/= 100 x 10 (platelet transfusion not alled to achieve this) d. Bilirubin \= 1.5 x ULN (or \= 3.0 x if ULN if Gilbert's syndrome) e. AST and ALT \= 3.0 x ULN (or \= 5 x ULN if the liver has tumor involvement f. Calculated creatinine clearance \>/= 60 mL/min using Cockcroft-Gault formula
* Patient is non-fertile or agrees to use adequate methods of contraception or agrees to refrain completely from heterosexual intercourse during the study and for 6 months (for female and male patients alike) after the last dose of study intervention.
* May be HIV positive if the following conditions are met:
1. CD4 + T-cell count \>/= 350 cells/uL
2. HIV viral load \< 400 copies/ml prior to enrollment
3. No history of acquired immunodefficiency syndrome (AIDS) defining opportunistic infections
* Known hepatitis B infection mush have negative serum HbsAg. Patients with known hepatitis C virus infection must have a viral load below the limit of quantification Japan sites only: HBc antibody or HBsantibody tests should be performed if HBsAg is negative. If HBc antibody or HBs antibody tests are positive, HBV DNA quantitative tests should be performed to confirm that HBV DNA is negative.
Exclusion Criteria:
* Patient has received prior treatment at any time with a cell cycle checkpoint inhibitor (eg, CHK1 and/or CHK2, WEE1, or ATR inhibition)
* Patient has a known allergy or sensitivity to any component of SMP-3124LP, including the inactive ingredients
* Patient has received treatment with systemic anticancer therapy, radiotherapy, or investigational therapy within 14 days prior to Study Cycle 1 Day 1. (Palliative radiotherapy with a limited field of radiation within 2 weeks will be permitted.)
* Patient has undergone a major surgical procedure ≤ 28 days, or minor surgical procedure ≤ 7 days, prior to Cycle 1 Day 1
* Patient has used strong CYP1A2 or 2D6 inhibitors within 14 days or 5 half-lives, whichever occurs first, prior to Cycle 1 Day 1 (examples of restricted CYP1A2 and CYP2D6, P-gp, and/or BCRP inducers, inhibitors, or substrates are presented in Table 16)
* Patient has central nervous system metastasis or leptomeningeal disease
* Prior or concurrent malignancy whose natural history or treatment would have a significant potential to interfere with the safety or efficacy assessments of the investigational regimen
* Patient has an abnormal ECG that is clinically significant, including a corrected QT interval (corrected using Fridericia's correction formula \[QTcF\]) \> 470 msec; and/or a history of Torsade de Pointes
* Patient has a left ventricular ejection fraction \< 45% by echocardiogram (ECHO)
* Patient has clinically significant cardiac disease including heart failure (eg, New York Heart Association, Class III or IV)
* Patient has an active, uncontrolled, bacterial, viral, or fungal infection requiring parenteral antimicrobial within 1 weeks prior to Cycle 1 Day 1
* Patient is pregnant (as evidenced by a positive serum or urine pregnancy test) or is breastfeeding. Female breastfeeding patients may be enrolled if they interrupt breastfeeding. Breastfeeding should not be resumed for at least 6 months after the last dose of study drug.
For sites in Japan only: In addition to the above, any patient deemed likely to be pregnant based on medical interview will be excluded from the study.
* Patient with ovarian cancer
1. Has a history of bowel obstruction related to their underlying disease within 3 months prior to Study Day 1
2. Has platinum-refractory disease. Platinum refractory is defined as progression during platinum-based chemotherapy
* Patient has any other medical or psychiatric condition that, in the opinion of the investigator, might interfere with their participation in the trial or interfere with the interpretation of trial results
* Patient is taking a prohibited medication at baseline.
Kashiwa-shi, 277-8577, Japan
[email protected] / No phone
Status: Recruiting
Denver, Colorado, 80218, United States
[email protected] / 720-754-2610
Status: Recruiting
Columbus, Ohio, 43210, United States
[email protected] / 614-292-4231
Status: Recruiting
Nashville, Tennessee, 37203, United States
[email protected] / No phone
Status: Recruiting
Nashville, Tennessee, 37232, United States
[email protected] / 800-811-8480
Status: Recruiting
Houston, Texas, 77030, United States
No email / No phone
Status: Recruiting