A Study to Evaluate eFT508 Alone and in Combination With Avelumab in Subjects With MSS Colorectal Cancer


About this study

This is a Phase 2, open-label, 2-part, multicenter study in subjects with MSS relapsed/refractory colorectal cancer. The primary objective of Part 1 is to evaluate the safety and tolerability of escalating doses of eFT508 in combination with a fixed dose of avelumab to determine the maximum tolerated dose (MTD) of eFT508 and to select a recommended dose for Part 2. The primary objective of Part 2 is to evaluate antitumor activity of eFT508 at the recommended dose in combination with avelumab or eFT508 monotherapy. Parts 1 and 2 will also evaluate pharmacokinetics (PK) and pharmacodynamics.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • ECOG performance status of 0, 1, or 2.
  • Pathologically documented diagnosis of colorectal adenocarcinoma.
  • Progressed on or intolerant of at least 2 prior cancer therapy regimens administered for metastatic disease.
  • Completion of all previous therapy (including surgery, radiotherapy, chemotherapy, immunotherapy, or investigational therapy) for the treatment of cancer ≥3 weeks before the start of study therapy. 
  • Part 2 only:   Presence of radiographically measurable disease (defined as the presence of ≥1 lesion that measures ≥10 mm [≥15 mm for lymph nodes]). Measurable disease that was previously radiated is only permitted if progressing.
  • Agrees to undergo a pretreatment and a post-treatment biopsy.
  • Microsatellite stable disease determined by IHC and/or polymerase chain reaction (PCR). - Adequate bone marrow function - Adequate hepatic function - Adequate renal function
  • Normal coagulation profile.
  • Negative antiviral serology.
  • Female subjects of childbearing potential must not be pregnant or breastfeeding.
  • Willingness to use protocol-recommended methods of contraception or to abstain from heterosexual intercourse from start of therapy until at lest 30 days after the last dose of study therapy.
  • Life expectancy of ≥3 months.

Exclusion Criteria:

  • History of another malignancy except for adequately treated local basal cell or squamous cell carcinoma of the skin; in situ cervical or breast carcinoma; adequately treated, papillary, noninvasive bladder cancer; other adequately treated Stage 1 or 2 cancers currently in complete remission, or any other cancer that has been in complete remission for ≥2 years. 
  • Known symptomatic brain metastases requiring ≥10 mg/day of prednisolone (or its equivalent).
  • Significant cardiovascular disease. - Significant screening ECG abnormalities.
  • Active autoimmune disease that might deteriorate when receiving an immunostimulatory agent.
  • Known history of colitis, inflammatory bowel disease, pneumonitis, or pulmonary fibrosis. 
  • Ongoing risk for bleeding due to active peptic ulcer disease or bleeding diathesis.
  • Evidence of an ongoing systemic bacterial, fungal, or viral infection.
  • Any condition that may impact the subject's ability to swallow oral medications.
  • Major surgery within 4 weeks before the start of study therapy.
  • Prior solid organ or bone marrow progenitor cell transplantation.
  • Prior therapy with any known inhibitor of MNK-1 or MNK-2.
  • Prior therapy with any of the following: PD-1, PD-L1, CTLA4 antibody, or any other drug targeting T cell checkpoint pathways.
  • Prior high dose chemotherapy requiring stem cell rescue.
  • Intolerance to or prior severe (≥Grade 3) allergic or anaphylactic reaction to infused antibodies or infused therapeutic proteins. 
  • Vaccination within 4 weeks of the first dose of avelumab and while on study.
  • Ongoing immunosuppressive therapy.
  • Use of a strong inhibitor or inducer of cytochrome P450 3A4 (CYP3A4) within 7 days prior to the start of study therapy or expected requirement for use of a strong CYP3A4 inhibitor or inducer during study therapy.
  • Previously received investigational product in a clinical trial within 30 days or within 5 elimination half lives (whichever is longer) prior to the start of study therapy, or is planning to take part in another clinical trial while participating in this study.
  • Has any illness, medical condition, organ system dysfunction, or social situation, including mental illness or substance abuse, deemed by the Investigator to be likely to interfere with a subject's ability to sign informed consent, adversely affect the subject's ability to cooperate and participate in the study, or compromise the interpretation of study results.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Joleen Hubbard, M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office

(855) 776-0015

Scottsdale/Phoenix, Ariz.

Mayo Clinic principal investigator

Tanios Bekaii-Saab, M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office


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