Study to Evaluate Safety and Preliminary Efficacy of MOR208 With Idelalisib or Venetoclax in R/R CLL/SLL Patients Pretreated With BTKi (COSMOS)


About this study

This is a two-cohort, multicenter, open-label study of MOR00208 combined with idelalisib or venetoclax in adult patients with R/R CLL or R/R SLL pretreated with a BTK inhibitor (e.g., ibrutinib) as single agent or as part of combination therapy.

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.

Major Inclusion Criteria

Diagnosis/Trial Population

  • Chronic lymphocytic leukemia (CLL) or small lymphocytic lymphoma (SLL):
    • history of diagnosis of CLL or SLL that meets IWCLL diagnostic criteria
    • histologically confirmed diagnosis of SLL by lymph node biopsy
    • indication for treatment as defined by the IWCLL guidelines
  • Patients must have both of the following:
    • relapsed or refractory disease while receiving a BTKi therapy or intolerance of such therapy
    • single-agent or combination therapy with a BTKi for at least one month must be the patient's most recent prior anticancer therapy
  • ECOG performance status of 0 to 2
  • Patients with a past medical history of autologous or allogeneic stem cell transplantation must exhibit full hematological recovery

Laboratory Values

• Patients must meet adequate bone marrow function and adequate hepatic and renal function

Other Inclusion Criteria

• Females of childbearing potential must use a highly effective method of contraception

Major Exclusion Criteria


• Patients who have:

  • Non-Hodgkin's lymphomas other than CLL/SLL
  • Transformed CLL/SLL or Richter's syndrome
  • Active and uncontrolled autoimmune cytopenia

Previous and Current Treatment

  • Patients who have received treatment with a BTK inhibitor within 5 days prior to Day 1 dosing
  • Patients who have, within 14 days prior to D1 dosing:
    • Not discontinued CD20-targeted therapy, chemotherapy, radiotherapy, investigational anticancer therapy or other lymphoma specific therapy
    • Systemic corticosteroids in doses greater than prednisone equivalent to 20 mg/day with the exception of patients with signs of rapidly progressing disease
    • Received live vaccines with the exception of vaccination against influenza with inactivated virus or for pneumococcal diseases

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

Jacksonville, Fla.

Mayo Clinic principal investigator

Asher Alban Chanan Khan, M.B.B.S., M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office

(855) 776-0015

Rochester, Minn.

Mayo Clinic principal investigator

Sameer Parikh, M.B.B.S.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office

(855) 776-0015

More information


Publications are currently not available

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