~4 spots leftby Apr 2026

Tadalafil to Overcome Immunosuppression During Chemoradiotherapy for IDH-wildtype Grade III-IV Astrocytoma

Recruiting in Palo Alto (17 mi)
Overseen byJiayi Huang, M.D.
Age: 18+
Sex: Any
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Phase 1
Waitlist Available
Sponsor: Washington University School of Medicine
No Placebo Group
Approved in 2 Jurisdictions

Trial Summary

What is the purpose of this trial?

Increasing preclinical and clinical data have shown that myeloid-derived suppressor cells (MDSCs) may represent a significant driver of immunosuppression in glioblastoma (GBM, grade IV astrocytoma) and a potential mechanism of treatment resistance to chemoradiotherapy. Tadalafil, an FDA-approved drug with inexpensive cost and excellent safety profile, has been shown to effectively reduce MDSCs and restore T-cell activation in the peripheral blood and in the tumor microenvironment. The purpose of this study is to investigate the impact of targeting MDSCs in newly diagnosed IDH-wildtype grade III-IV astrocytoma by combining tadalafil with standard of care radiation therapy (RT) and temozolomide (TMZ).

Eligibility Criteria

Inclusion Criteria

Adequate organ and bone marrow function as defined below: Absolute neutrophil count (ANC) ≥ 1,500 cells/mm3; Platelets ≥ 100,000 cells/mm3; Hemoglobin > 9.0 g/dL (Note: the use of transfusion or other intervention to achieve Hgb >9.0 g/dL is acceptable); Total bilirubin ≤ 1.5 upper limit of normal (ULN) AST (SGOT) and ALT (SGPT) ≤ 3 x ULN Creatinine ≤ 1.5 ULN or creatinine clearance ≥ 60 mL/min If there is history of human immunodeficiency virus (HIV) infection, patients must be on effective antiretroviral therapy, and HIV viral load must be undetectable within 6 months of study enrollment. If there is history of chronic hepatitis B virus (HBV) infection, patients must have either been treated or are on suppressive therapy (as indicated), and HBV viral load must be undetectable. If there is history of hepatitis C virus (HCV) infection, patients must have been treated, and HCV viral load must be undetectable. Females of childbearing potential (defined as a female who is non-menopausal or surgically sterilized) must be willing to use an acceptable method of birth control (i.e., hormonal contraceptive, intra-uterine device, diaphragm with spermicide, condom with spermicide, or abstinence) for the duration of the study. Should a woman become pregnant or suspect she is pregnant while participating in this study, she must inform her treating physician immediately. Able to understand and willing to sign an IRB-approved written informed consent document (legally authorized representative permitted).
Must have recovered from the effects of surgery, postoperative infection, and other complications sufficiently that they can proceed with RT and TMZ.
You are scheduled to receive a specific radiation treatment known as standard fractionated RT of 60 Gy with concurrent TMZ.
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Exclusion Criteria

Severe, active co-morbidity, defined as follows: Unstable angina, angina requiring treatment with nitrates, positive cardiac stress test without evidence of subsequent effective cardiac intervention within 90 days of planned tadalafil administration Myocardial infarction, coronary artery bypass graft surgery, or percutaneous coronary angioplasty or stent within the 90 days of planned tadalafil administration New York Heart Association grade II or greater congestive heart failure within 6 months Serious and inadequately controlled arrhythmia Hypotension (<90/50 mm Hg) or uncontrolled hypertension (>170/100 mm Hg) Left ventricular outflow obstructions, such as aortic stenosis Stroke within the last 6 months Acute bacterial or fungal infection requiring intravenous antibiotics. Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects; note, however, that laboratory tests for coagulation parameters are not required for entry into this protocol. Active peptic ulcer disease. End-stage renal disease (ie, on dialysis or dialysis has been recommended). Unilateral blindness, hereditary retinal disorder, including retinitis pigmentosa. Patients treated on any other therapeutic clinical protocols within 30 days prior to registration. Inability to undergo contrast-enhanced MRI (e.g., due to safety reasons, such as presence of a pacemaker, or severe claustrophobia). Pregnant or breastfeeding. Women of childbearing potential must have a negative pregnancy test within 14 days of study entry. Patients with psychiatric illness/social situations, including alcohol or drug abuse that in the investigator's opinion will prevent administration or completion of protocol therapy.
Concurrent nitrate, alpha-blocker, guanylate cyclase stimulators (eg, riociguat), or cytochrome P-450 3A4 (CYP3A4) inhibitor use. CYP3A4 inhibitors include ketoconazole, itraconazole, and ritonavir.
Prior cranial RT or RT to the head and neck where potential field overlap may exist
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Treatment Details

Interventions

  • Tadalafil (Phosphodiesterase Inhibitor)
Participant Groups
1Treatment groups
Experimental Treatment
Group I: TadalafilExperimental Treatment1 Intervention
* Tadalafil will be given orally once daily for a total of 60 days at a weight-normalized dose as follows: * 10 mg/day if weight ≤63.5 kg * 15 mg/day if weight \>63.5 kg and ≤104.3 kg * 20 mg/day for weight \>104.3 kg * Standard of care fractionated radiation therapy (RT) to 60 Gy in 30 daily fractions will be administered in this study. * Concurrent temozolomide (TMZ) will be administered as per standard of care, i.e., continuously (Monday through Sunday) from Day 1 of RT to the last day of RT at a daily oral dose of 75 mg/m\^2 at the discretion of treating medical oncologist. * Adjuvant therapy will administered as per standard of care. Typically, this consists of adjuvant TMZ initiated 4 to 6 weeks after completion of RT for 6 cycles at 150-200 mg/m\^2 PO per day on Days 1-5 of every 28-day cycle. Tumor-treating fields or Optune device (Novocure) as per routine clinical care during adjuvant TMZ is permitted at the discretion of the treating physician.

Tadalafil is already approved in United States, European Union for the following indications:

🇺🇸 Approved in United States as Cialis for:
  • Erectile dysfunction
  • Pulmonary hypertension
🇪🇺 Approved in European Union as Tadalafil for:
  • Erectile dysfunction
  • Pulmonary hypertension

Find a Clinic Near You

Research Locations NearbySelect from list below to view details:
Washington University School of MedicineSaint Louis, MO
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Who Is Running the Clinical Trial?

Washington University School of MedicineLead Sponsor

References