Sponsor: Sumitomo Pharma America, Inc. (industry)
Phase: 1/2
Start date: Aug. 14, 2024
Planned enrollment: 120
SMP-3124LP is an investigational, intravenous formulation of SMP-3124 for advanced solid tumors. It is being studied in an ongoing, first-in-human phase 1/2 trial; the available efficacy and safety findings are preliminary. (ascopubs.org)
SMP-3124 inhibits checkpoint kinase 1 (CHK1), a protein involved in the response to DNA damage and cell-cycle control. SMP-3124LP packages the inhibitor in a PEGylated liposome. This formulation is intended to improve delivery to tumors and limit exposure of healthy tissue, but a clinical advantage over other CHK1 inhibitors has not been established. (ascopubs.org)
In a 2026 conference abstract, 5 of 35 efficacy-evaluable patients (14%) had a partial response and 12 had stable disease, for a disease-control rate of 49%. Partial responses occurred in two patients with platinum-resistant ovarian cancer, two with anal squamous-cell carcinoma, and one with colorectal cancer. These results come from an early, uncontrolled study and do not establish clinical benefit. (ascopubs.org)
Among 42 enrolled patients in the abstract, the most common treatment-related adverse events were neutropenia (45%), infusion reactions (38%), thrombocytopenia (36%), anemia (24%), and leukopenia (21%). Grade 3–4 neutropenia occurred in 33%. Dose-limiting thrombocytopenia occurred at higher doses; one patient also had dose-limiting febrile neutropenia. (ascopubs.org)
Last updated: Sep 2026
Goal: Determine a recommended phase 2 dose and assess the safety, pharmacokinetics, and preliminary antitumor activity of SMP-3124LP.
Patients: Adults with advanced, recurrent, or metastatic cancer that has progressed after standard therapy, with no remaining alternative expected to improve overall survival. Dose escalation includes platinum-resistant ovarian cancer, triple-negative breast cancer, anal or head and neck squamous cell carcinoma, non-small cell lung cancer, and uterine serous cancer. Expansion focuses on platinum-resistant ovarian cancer, triple-negative breast cancer, and anal squamous cell carcinoma. ECOG performance status must be 0–2, with adequate organ function; patients with CNS metastases or prior checkpoint-inhibitor treatment are excluded.
Design: Global, multicenter, open-label, nonrandomized, first-in-human dose-escalation and dose-expansion study. Dose escalation and optimization precede disease-specific expansion at the recommended phase 2 dose. There is no control arm.
Treatments: SMP-3124LP is given by IV infusion, initially every 2 weeks; an every-3-week schedule may also be evaluated. Expansion patients receive the dose selected from escalation. SMP-3124LP is a PEGylated liposomal formulation of an inhibitor of CHK1, a kinase involved in DNA-damage response and cell-cycle control. Preliminary uncontrolled results reported partial responses in 5 of 35 evaluable patients (14%); among 42 enrolled patients, neutropenia and infusion reactions were common, and dose-limiting thrombocytopenia occurred at higher doses. These findings do not establish clinical benefit.
Outcomes: Primary measures are dose-limiting toxicities during the first 28 days to inform dose selection, adverse and serious adverse events, and objective response rate. Secondary measures include drug exposure (Cmax and AUC) and duration of response by RECIST v1.1.
Burden on patient: High. Repeated clinic visits for IV infusions every 2 or 3 weeks, safety monitoring, pharmacokinetic blood sampling, and tumor assessments are expected. Dose-escalation participation may require particularly intensive early monitoring; the provided information does not specify a mandatory research biopsy.
Last updated: Sep 2026
Caution: ClinicalTrials.gov appears to have newer eligibility criteria than the version saved here. Review the current criteria in ClinicalTrials.gov.
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.
Kyoto, 606-8507, Japan
[email protected] / No phone
Status: Recruiting
Kashiwa-shi, 277-8577, Japan
[email protected] / No phone
Status: Recruiting
Los Angeles, California, 90048, United States
[email protected] / 310-423-2133
Status: Recruiting
Denver, Colorado, 80218, United States
[email protected] / 720-754-2610
Status: Recruiting
Chicago, Illinois, 60611, United States
[email protected] / 312-695-9367
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
Seattle, Washington, 98105, United States
[email protected] / 206-606-7438
Status: Recruiting