Quadruplets, Immune-Based Regimens Slated to Expand the Frontline Myeloma Paradigm

Matthew James Pianko, MD

Daratumumab (Darzalex)-based quadruplet regimens and cutting-edge immune-based therapies are positioned to become potential standard options in frontline multiple myeloma treatment, said Matthew James Pianko, MD, adding that the frontline setting is a prime target for improved and novel therapeutics.

“The treatment of patients with newly diagnosed multiple myeloma is an evolving area,” said Pianko. “The drug combinations we have now are highly effective, but many of the options coming [down the pike] could allow us to provide deeper responses for patients. Data supporting the use of quadruplet regimens for [this patient population] are also coming.”

“Future trials will help us [determine] which of the triplet backbones will be the best partner for a CD38-based quadruplet regimen. However, before quadruplets can really be considered a true new standard of care, more data are required,” added Pianko, a clinical assistant professor at the University of Michigan Health.

During the 2021 Institutional Perspectives in Cancer webinar on multiple myeloma, faculty from the University of Michigan Health zeroed in on therapeutic updates in the frontline and relapsed settings and how more novel approaches, including CAR T-cell therapy, are shifting best practices in the paradigm. Pianko, who chaired the event, noted that the webinar had a key role in helping to establish and connect the academic institution with local referring community providers to discuss cutting edge developments in myeloma treatment.

In an interview with OncLive®, Pianko reflected on the abovementioned topics—specifically how he approaches patients with newly diagnosed multiple myeloma, and differentiating options based on transplant eligibility, as well as which emerging immune-based therapies he is most intrigued by.

OncLive®: How do you approach selecting a frontline treatment regimen for patients with newly diagnosed myeloma?

Pianko: My approach to the treatment of [patients with] newly diagnosed multiple myeloma incorporates a very patient-centric [tactic]. I look at multiple factors specific to the patient, which can help to guide treatment decisions, [including] age, other medical conditions, cardiovascular risk, pre-existing neuropathy, and transplant eligibility. These factors play into how we select treatment.

Recent data from several trials have allowed for multiple choices in the frontline setting that would be appropriate for both transplant-eligible and -ineligible patients with multiple myeloma. Largely, tailoring therapy to a specific patient is becoming more possible with much of the data we have in newly diagnosed multiple myeloma.

How do you adapt treatment selection to patients with transplant-eligible vs -ineligible multiple myeloma in the frontline setting?

For the transplant-eligible population, our current practice is to generally use triplet regimens, [such as] bortezomib [Velcade], lenalidomide [Revlimid], and dexamethasone [VRd] or carfilzomib [Kyprolis], lenalidomide, and dexamethasone [KRd]. The patient’s age, cytogenetic risk, and pre-existing neuropathy can help us to choose [between these triplet regimens].

The ENDURANCE trial [NCT01863550] was a large, randomized, phase 3 study that compared VRd with KRd and showed that VRd was not superior to KRd. The study highlighted that there is a known difference in the adverse effect [AE] profiles of these [triplets]. The patients getting VRd had a high incidence of treatment discontinuation [because of] treatment-related AEs, including peripheral neuropathy, which is associated with bortezomib. In the KRd combination, high incidences of cardiac, pulmonary, and renal toxicities [were observed].

Largely, there [doesn’t] seem to be a difference in terms of progression-free survival [PFS] between the 2 groups, but we did see a difference in the AE profiles. The basis for choosing one [triplet] over the other can be guided by the expected AEs and driven by the [individual] patient.

In my practice, I tend to favor KRd in young patients with newly diagnosed multiple myeloma without significant medical comorbidities and independent of cytogenetic risk. [This is] because of the peripheral neuropathy bortezomib [can cause] that can be permanent. For many patients who have a life expectancy of potentially at least 1 decade, the cumulative quality-of-life burden of daily pain from peripheral neuropathy is a significant issue to consider.

My discussion with my patients often discusses the risk of peripheral neuropathy and cardiopulmonary AEs from carfilzomib. Ultimately, after discussing [these risks] with the patient, we together choose which [treatment] is the most appropriate way forward.

In the transplant-ineligible patient population, there are younger patients who have medical comorbidities that might preclude a transplant, and we have our older patients. Generally, [transplant ineligibility] is in the range of 75 to 80 years old. That is when we could classify someone as being potentially transplant ineligible but [we need to consider] geriatric and frailty assessments that can help guide us.

For patients who are intermediate-fit or frail, we might consider a doublet regimen, such as lenalidomide plus dexamethasone [Rd]. The inclusion of daratumumab to this doublet [based on] the MAIA trial [NCT02252172] showed us that [Rd plus daratumumab] is a viable approach for patients with newly diagnosed, transplant-ineligible multiple myeloma. The toxicity profile of daratumumab pairs well [with Rd] in this [patient population] to be [considered] a potential standard of care.

Other regimens include the VRd-lite regimen, which uses a modified dose and schedule for bortezomib and lenalidomide. That is another option for our transplant-ineligible patients.

A study was recently published looking at a modified schedule of lenalidomide/dexamethasone where patients would get [the doublet] for 9 cycles and then were able to de-escalate [treatment] and drop the dexamethasone. It seems like this approach is another viable option for our transplant-ineligible patients, particularly those with intermediate-fit or frail disease.

The take-home message is that there are multiple options that we can choose from in both the transplant-eligible and -ineligible patient populations.

What is the current role of daratumumab in the up-front setting? Do you anticipate daratumumab-based quadruplet regimens emerging as the standard of care for this patient population?

The role of daratumumab in the frontline setting for multiple myeloma is an evolving one. Based on the MAIA trial, Rd plus daratumumab is now an FDA-approved regimen for patients with newly diagnosed, transplant-ineligible multiple myeloma. We have seen promising early data from the GRIFFIN study [NCT02874742], which looked at the quadruplet combination of daratumumab plus VRd vs VRd alone.

We saw [from the GRIFFIN trial] that the addition of daratumumab to this regimen was another viable approach. We saw superior depth of response and higher rates of stringent complete responses in up to 60% of patients [treated with] daratumumab plus VRd vs about 20% for the triplet regimen. We also saw a higher degree of minimal residual disease [MRD]–negative disease with the quadruplet [compared with the triplet]. The safety profile [with the quadruplet] was acceptable, and namely, the stem cell collection did not seem to be compromised by the inclusion of daratumumab in the up-front setting. Patients were able to successfully collect stem cells without any compromise in the quadruplet arm.

There is a large, international, phase 3 trial called the Perseus trial [NCT03710603], which is going to further evaluate the quadruplet vs triplet combinations that were evaluated in the GRIFFIN trial. [The results of the Perseus trial] should provide further information as to whether [daratumumab plus VRd] could be a potential standard [treatment for patients with] newly diagnosed multiple myeloma.

The KRd triplet [is also] a potential backbone for daratumumab-based therapy and there have also been some exciting studies looking at that [quadruplet]. At the University of Alabama at Birmingham, the phase 2 MASTER trial [NCT03224507] was led by Luciano J. Costa, MD, and looked at daratumumab plus KRd as a potential approach in newly diagnosed multiple myeloma.

There was also a recently reported small study out of Memorial Sloan Kettering Cancer Center called the MANHATTAN trial, which looked at weekly KRd plus daratumumab. In about 41 patients enrolled in the non-randomized trial, the overall response rate was 100%, and 39 patients had a very good partial response or better. Also, these patients had an exceedingly high rate of MRD-negative disease. This is a promising potential option, but randomized data need to be evaluated [because] this was a small, non-randomized study.

Speaking to that, C. Ola Landgren, MD, of the University of Miami Miller School of Medicine, is leading a multicenter, phase 3 trial called ADVANCE [NCT04268498] that is looking at VRd vs KRd vs daratumumab plus KRd. It is a 3-arm, randomized trial that is likely to provide further data on the feasibility and efficacy of using [these triplets and quadruplets] in the up-front setting.

[Determining] the standard of care for patients with newly diagnosed multiple myeloma has become complicated these days. There are several trials in progress that can help answer this question soon. However, currently, daratumumab is a promising potential partner for each of our backbone triplets. From my perspective, phase 3 data are required to cement a quadruplet option as a standard of care for newly diagnosed multiple myeloma.

I anticipate that these upcoming trials in progress will show us whether a quadruplet regimen is the way to go for newly diagnosed disease, but those data are not available yet.

Are toxicities a concern when considering quadruplet therapy?

The management of toxicities from multi-drug regimens in newly diagnosed myeloma is an important consideration. When looking at combinations that include daratumumab and immunomodulatory drugs, such as lenalidomide, then cytopenias, low blood counts, and low neutrophil counts can certainly be an issue early on in treatment. Dose modifications of lenalidomide and potential use of growth factor support can be helpful in maintaining the blood counts to a sufficient level so that we can continue to give patients the highest doses [of the medications] to achieve deep remissions.

The peripheral neuropathy [associated with] bortezomib requires careful management. Much of the published data from these duties included twice-weekly subcutaneous bortezomib on days 1, 4, 8, and 11 at 1.3 mg/m2. In the community [setting] and in our practice, we use a modified schedule of once-weekly bortezomib that has a much lower rate of peripheral neuropathy.

What is on the horizon in terms of immunotherapy in multiple myeloma? Will this treatment approach ever be considered up front?

Much progress [is being done regarding] the treatment of patients with relapsed/refractory multiple myeloma. [We are starting to] use immunotherapeutic drugs to try to harness the power of the immune system to attack myeloma. Myeloma has been such an exciting area of practice with all these new agents that have been coming out for patients with relapsed disease.

There are several drugs in this setting that are exciting and could potentially be considered as options for the newly diagnosed patient population. However, we are still several years away from [those drugs being introduced to the armamentarium].

Data presented during the 2020 ASH Annual Meeting showed that a host of bispecific antibodies targeting BCMA [are being investigated]. BCMA is a receptor protein on the surface of myeloma cells that seems to be universally expressed on myeloma plasma cells. [BCMA] is a good target for immune-based treatments and the advantage of bispecific antibodies is that they are off-the-shelf agents. They clearly offer a way to provide rapid responses [to patients].

Looking ahead, the current challenges of cytokine release syndrome [CRS] and dealing with the toxicities of [cellular therapies] are important to figure out, especially if there is any relationship between CRS and tumor burden. Bringing these agents into the frontline setting with patients who have a much larger tumor burden is going to be something to carefully consider in future trials. Yet, these drugs are not far enough along to be considered for frontline treatment, but they [yield] potent effects and can be administered off-the-shelf to patients.

It will be fascinating to see how the bispecific antibodies are incorporated into frontline treatment, as well as the early-relapse setting, but we are several years away from that. We have yet to see among many competitors in the bispecific antibody race which one will become available first and which will be the best. Will we have multiple options in this category? All these questions have yet to be answered.

CAR T-cell therapy is another platform that has been very exciting. With the recent FDA approval of idecabtagene vicleucel [Abecma], we have another option for heavily relapsed patients. It will be interesting to see if we can use CAR T-cell therapy in earlier lines of therapy and what effects [that would yield].

CAR T-cell therapy does require a fair amount of preparation, planning, manufacturing time, and lead time, so the logistical considerations for administering CAR T-cell therapy are significant. Likely, if [this treatment] is going to be considered in the frontline setting, patients will receive other agents prior as preparation for CAR T-cell therapy.

There is a fascinating future for immunotherapy in myeloma. The years to come will show us whether [bispecific antibodies and CAR T-cell therapies] have a role for the treatment of newly diagnosed disease.

The other thing to consider is treatment with checkpoint inhibitors has had a checkered history in myeloma. PD-1 inhibitors were shown to be toxic in combination with lenalidomide or pomalidomide [Pomalyst]. The checkpoint blockade approach, which has been successful in many other tumor types, has not had a future in myeloma; however, other novel immune checkpoints are being considered in the relapsed setting with TIGIT and LAG3 [inhibitors]. These are agents are being evaluated in ongoing trials.

There are other potential approaches we can use to modulate the immune system for the treatment of patients with multiple myeloma, but it takes many years to do these studies and establish safety and [efficacy]. It will be some time before we have other immune therapies applied to the frontline setting.