Category: Clinical Trials

The Story of Ibrutinib in Mantle Cell Lymphoma

Picture1By Peter Martin, MD

Just over one year ago, in November 2013, the United States Food and Drug Administration (FDA) approved the oral drug ibrutinib for patients with previously treated mantle cell lymphoma (MCL). The FDA based its decision upon promising results from the PCYC-1104 trial that took place at several centers around the world, including Weill Cornell Medical College (WCMC). During the 56th Annual Meeting of the American Society of Hematology, long-term follow up from the PCYC-1104 trial was presented. At the two year time point, roughly one third of patients remain free from progression. Moreover, serious side effects appear to become less frequent with time.

Because bias and chance can sometimes lead to promising results, investigators from around the world, including WCMC performed a second trial (MCL2001) to evaluate the effects, good and bad, of ibrutinib in 120 patients with previously treated MCL. Preliminary data from MCL2001 was also presented during ASH, and they appear to be consistent with the PCYC-1104. With roughly 15 months of follow up, two-thirds of patients responded and responses lasted for a little more than one year on average. No new side effects were identified.

Finally, preliminary results from the MCL4001 Early Access Program (EAP), were presented. The EAP was designed to provide ibrutinib to patients with relapsed or refractory MCL prior to its approval by the FDA and was open at several sites around the world, including WCMC. One hundred forty-nine patients with MCL received daily oral ibrutinib and were followed for safety. Like the PCYC-1104 and MCL2001 trials, MCL4001 confirmed the safety of ibrutinib. Less than 10% of patients stopped ibrutinib due to an adverse event and most patients continued to receive ibrutinib through the EAP until the FDA approved it. Taken together, these three trials confirm the important role of ibrutinib in the management of mantle cell lymphoma.

Unfortunately, despite the recognized efficacy of ibrutinib in patients with MCL, roughly one-third of patients are resistant and among those that respond, secondary resistance to ibrutinib is common. In a retrospective cohort study we identified 32 patients at WCMC and Ohio State University, who experienced progression of lymphoma while receiving ibrutinib. There was no clear association between prior number of therapies, ibrutinib response, morphology, Ki67 prior to ibrutinib, response to ibrutinib, duration of ibrutinib, or choice of subsequent therapy and overall survival. Ultimately primary and secondary ibrutinib resistance was associated with poor clinical outcomes, and there were no identifiable predictors of response to subsequent therapy following development of ibrutinib resistance.

These data underscore the importance of ongoing research in MCL. As we learn more about potential mechanisms of resistance to ibrutinib we are able to design rational combinations that build on the remarkable safety and activity of the drug. Moreover, there is clearly a need for new treatments that have the potential to help patients that experience progression of lymphoma while on ibrutinib. Fortunately, investigators at WCMC and around the world have identified the emergence of this new unmet need and are working on new treatment options. Stay tuned to the WCMC Lymphoma Program Blog for new developments.

Circulating Memory T-cell Isolated from Hodgkin Lymphoma Patients Display Evidence of Exhaustion and Chronic Activation

Picture2By Jia Ruan, MD, PhD

Although Hodgkin Reed-Sternberg (HRS) cells comprise only a small number of tumor cells, their number is outweighed by their relative importance as the orchestrators of an inflammatory microenvironment that allows for the growth of Hodgkin Lymphoma (HL). The peritumoral CD4 and CD8 cells in patients with HL, display high expression of the receptor programmed death-1 (PD-1). PD-1 is involved in the functional impairment and “exhaustion” of T-cells. Recent data confirms that the effects of HL-mediated immune suppression may stretch beyond the tumor microenvironment, with reports of high levels of inflammatory cytokines and chemokines in patients with both newly diagnosed and relapsed HL.

In results presented from an abstract presented during the 2014 American Society of Hematology conference (ASH), we found that HL patients have evidence of chronic activation/exhaustion in their central memory and effector T-cells. Informed consent was requested for correlative blood testing was obtained from patients with both newly diagnosed and relapsed HL. For patients with progressive disease persistence of this phenotype is worthy of further investigation as to whether immune dysfunction results from or is caused by resistance to therapy. An answer to this question may provide the rationale for an immune targeted therapy in patients with relapsed or resistance HL.

Brentuximab Vedotin is Efficacious as First Line Salvage Therapy in Patients with Relapsed/Refractory Hodgkin Lymphoma Prior to Autologous Hematopoietic Cell Transplantation

Picture1By Peter Martin, MD

Brentuximab vedotin (BV), is an antibody drug conjugate that selectively binds to a protein called CD30 on the surface of cells (e.g., Hodgkin lymphoma cells) and delivers a payload of toxin (monomethyl auristatin E) directly to that cell; i.e., a Trojan horse approach to cancer therapy. In 2011, the United States Food and Drug Administration (FDA) approved BV based on a phase II trial in which BV demonstrated an overall response rate (ORR) of 75% and complete response rate (CR) of 34% in patients with Hodgkin lymphoma that had relapsed following autologous hematopoietic cell transplantation (AHCT). Given the promising data, investigators at City of Hope and Weill Cornell Medical College-New York collaborated to evaluate the use of BV prior to AHCT. The standard approach for patients that relapse after first-line therapy includes cytotoxic chemotherapy followed by AHCT. However, this approach can be challenging for some patients and may be associated with some short-term and long-term toxicity. Use of BV prior to AHCT may cause patients some side effects and improve their quality of life prior to AHCT. Preliminary data from this trial were presented yesterday at the 56th Annual Meeting of the American Society of Hematology (ASH).

All patients had biopsy proven Hodgkin lymphoma that had relapsed following therapy with ABVD, BEACOPP, or a combination +/- radiation. Patients were treated with a standard dose of BV intravenously every 3 weeks for a maximum of 4 cycles. Over two-thirds of patients responded, including one third of patients that obtained a CR) and roughly half of the patients were able to proceed to AHCT without receiving additional chemotherapy. Treatments were well tolerated by all patients and no transfusions were required or neutropenic fevers developed.

The results from this trial suggest that BV may be an efficacious option as a first line salvage therapy. It is well tolerated and does not hinder stem cell collection or engraftment. Additional studies will be required to confirm these results. Moreover, this study may lay the groundwork for future studies with promising combinations.