Abstract Patients with multiple myeloma (MM) who do not respond to initial therapy have worse outcomes than primary responders, and effective treatments are lacking in this population. However, the outcomes of primary refractory disease in the modern treatment era have not yet been studied. We reviewed patients with MM treated with triplet/quadruplet therapy at our institution to assess the incidence of primary refractory disease and the impact of salvage therapies in this population. We identified 1127 patients, of whom 1086 were evaluated for hematologic responses after 4 to 6 cycles. Of these, 93.3% (1013) had evidence of response, whereas 6.7% (73) had primary refractory disease. With a median overall survival (OS) of 51.3 months, patients with primary refractory disease had an increased risk of shorter survival in univariable and multivariable analyses (hazard ratio [HR], 3.5 [95% confidence interval (CI), 2.5-4.9]; HR, 4.3 [95% CI, 2.6-6.9], respectively). In the subgroup analysis of patients with primary refractory disease, those who received second-line autologous stem cell transplantation (ASCT) had increased second progression-free survival (20.9 vs 8.1 months; P < .01) and second OS (74.7 vs 31.3 months; P = .02) compared with patients who did not. We conclude that early progression remains a significant factor for shorter OS in the current era, and salvage ASCT could be the most beneficial option for this population.
Comparison of daratumumab-based regimens as second-line therapy in relapsed/refractory multiple myeloma.
e20032 Background: The introduction of anti-CD38 antibodies (daratumumab) in the treatment landscape of multiple myeloma (MM) has increased the progression-free survival (PFS) in recent years. Still, the ideal combination (Dara-IMiD vs. Dara-PI) of these drugs in patients with relapsed MM is unclear. Methods: We reviewed MM patients treated with daratumumab as second-line therapy at our institution from 2016 to 2022 to assess the outcomes with the different combination therapies. We used the Kaplan-Meier method to estimate PFS from the first relapse. Results: We identified 329 patients with a median age of 63.6 years (range: 27.1 – 90.4). Most of the patients received triplet induction therapy (95%) and upfront transplant (67%) as primary therapy. At the time of Dara initiation, 41% were refractory to IMiDs, 22% to PIs, 18% to both, and 18% to neither drug. Patients treated with Dara-IMiD had significantly better PFS than Dara-PI (28.7 months vs. 18.5 months, p < 0.01, respectively). In a subgroup analysis based on the FISH results, high-risk patients had similar PFS outcomes (24.3 vs. 10.2 months, p = NS, respectively), while standard-risk patients benefited significantly from the Dara-IMiD regimen (48.3 vs. 19.2 months, p < 0.01, respectively). Among patients treated with Dara-IMiD, those already refractory to IMiDs from the first line had significantly shorter PFS than those without IMiD resistance (14.9 vs. 43.3 months, p < 0.01, respectively). In addition, the lenalidomide-based combination resulted in significantly better PFS compared to pomalidomide in our cohort (40.5 vs. 19.2 months, p < 0.01, respectively). However, no difference was found in the IMiD refractory population (12.3 vs. 15.1 months, respectively). Finally, no significant differences were seen between Dara-IMiD and Dara-PI in patients only refractory to IMiDs (16.1 vs. 12.8 months, p = NS, respectively). Conclusions: While further studies are required to adjudicate the best combination, we conclude that Dara-IMiD might be more effective in patients with relapsed MM, especially for patients not refractory to IMiD at first line. [Table: see text]
Outcomes of patients with multiple myeloma refractory to different administration schedules of bortezomib.
e20011 Background: Drug refractoriness is an important factor determining choice of next therapy and prognosis in multiple myeloma (MM). It is debatable whether refractoriness to a drug varies among patients (pts) with MM progressing on different administration schedules of the drug. Outcomes of MM pts refractory to different doses of lenalidomide have been previously described, but similar data about proteasome inhibitors (PIs) are limited. In this study, we assessed the impact of refractoriness to different schedules of bortezomib (V) on outcomes with subsequent therapies in MM pts. Methods: We retrospectively reviewed MM pts at our center diagnosed between January 2004 and December 2018, who progressed on/ after receiving first line therapy with V containing regimens. At first relapse, we divided pts into 3 groups- MM progressing on or within 60 days of receiving (1) 1-1.3 mg/m2 V once weekly or more frequently (Standard Dose Refractory), (2) 1-1.3 mg/m2 V once every 2 weeks or less frequently (Low Dose Refractory), and (3) MM progressing at least 60 days after stopping V (Not Refractory). In addition to V, we classified pts as being refractory to cyclophosphamide and immunomodulatory drugs (IMiDs) at first relapse. We classified salvage regimens into daratumumab (Dara), PI, IMiD, PI+IMiD, and VDTPACE like regimens. We then assessed progression free survival (PFS) and overall survival (OS) for next line therapy, and for next V containing therapy using Kaplan Meier and Cox models. Results: A total of 302 pts were included. Median age at diagnosis was 62 years and 60% pts were male. Overall, 23%, 31%, and 27% were International Staging System (ISS) stage I, II, and III respectively; 40% had high risk FISH as per mSMART. Of the 302 pts, 134 (44%) pts received another V containing regimen after the first line therapy at any time during the disease course. Using a multivariable Cox model to adjust for ISS, high risk FISH, refractoriness to other drugs, duration of first line therapy, and treatment received at relapse, the Not Refractory Group had a better PFS for both 2nd line therapy and the next V containing line of therapy, while no significant differences were seen between the Standard Dose Refractory and Low Dose Refractory groups. OS differences followed the same trend but were not statistically significant (Table). Conclusions: On multivariable analysis, the PFS did not differ among standard dose vs low dose refractory pts, and both were significantly inferior to pts not refractory to V. These data suggest that refractoriness to V might not be a dose dependent phenomenon. [Table: see text]
Outcomes of patients with primary refractory multiple myeloma in the era of triplet and quadruplet induction therapy.
8051 Background: Patients with multiple myeloma (MM) that do not respond to initial therapy have worse outcomes compared to primary responders, and effective treatments are lacking in this population. However, the outcomes of primary refractory disease in the modern treatment era have not been studied. Methods: From 2007-2019, we reviewed MM patients treated with triplet/quadruplet therapy in our institution to assess the incidence of primary refractory disease and the impact of salvage therapies in this population. Primary refractory disease was defined as either progressive disease or stable disease at 4-6 cycles. The Kaplan-Meier estimates were used for survival probabilities. PFS and OS were calculated from MM diagnosis to progression, escalation/change of treatment, or death, respectively. For the primary refractory group, the second PFS and second OS were measured from the start of second-line therapy. The Cox regression model was used for multivariable analysis with the following variables (age, ISS, induction therapy, FISH, and bone marrow plasma cells at diagnosis). Results: We identified 1127 patients, of which 1086 were evaluated for hematologic response after 4-6 cycles. Of these, 93.3% (1013) had evidence of response, while 6.7% (73) had primary refractory disease. With a median OS of 50.7 months, patients with primary refractory disease had an increased risk for shorter survival in univariable and multivariable analysis (HR: 3.6, 95% CI = 2.61 – 4.96, HR = 3.89, 95% CI = 2.68 – 5.65, respectively). In subgroup analysis of primary refractory patients, the median second PFS and second OS from the first relapse were 11.9 months (95% CI: 8.7 – 17.3 months) and 43.4 (95% CI: 31.4– 75.9 months), respectively. Patients that received 2nd line ASCT had increased second PFS (20.9 vs. 8.1 months, respectively, p < 0.01) and second OS (74.7 vs. 31.3 months, respectively, p = 0.02) compared to patients that did not. Patients that took daratumumab as the second line did not have any significant survival differences compared to those who did not, p = NS. Conclusions: We conclude that early progression remains a significant factor for shorter OS in the current era, and salvage ASCT could be the most beneficial option for this population. [Table: see text]
Geographic disparities in Medicare telehealth utilization and access to specialized cancer care in the United States.
e13683 Background: Access to specialized cancer care varies by place of residence, partly due to differences in geographic proximity to designated cancer centers. Telehealth services can help alleviate some of these geographic disparities. In response to the COVID-19 pandemic, Medicare telehealth services were expanded rapidly. In this study, we sought to describe the geographic variations in Medicare telehealth utilization and their relationship with locations of designated cancer centers in the United States. We hypothesized that differences in telehealth utilization might be reflective of barriers to telehealth access for Medicare beneficiaries in these regions. Methods: We used the Medicare Telehealth Trends data file and calculated the proportion of Medicare users who used a telehealth service (% Telehealth Users) across all quarters of 2021. To obtain % Telehealth Users in a state, the number of telehealth users were divided by the total number of telehealth-eligible users. Then, using % Telehealth Users as a metric of telehealth utilization, we ranked all US states by overall % Telehealth Users, and % Telehealth Users in rural and urban locations. Finally, we correlated these ranks with the presence of an NCI (National Cancer Institute) Designated Cancer Center within the states. Results: The % Telehealth Users ranged from 15%-53% overall, 16%-54% for rural locations, and 14%-54% for urban locations, across lowest ranked to highest ranked states. The 5 lowest ranking states and their respective % Telehealth Users overall were- Wyoming (20%), Montana (20%), Iowa (20%), South Dakota (18%), Nebraska (17%), and North Dakota (15%). The lowest ranking states in terms of rural % Telehealth Users were Montana, Kansas, Iowa, Tennessee, Wyoming (19% each), and South Dakota and Nebraska (16% each). The lowest ranking states in terms of urban % Telehealth Users were Montana (20%), Wyoming (20%), Nebraska (19%), South Dakota (16%), and North Dakota (14%). 4 out of 6 states overall, 3 out of 7 in the rural category, and 4 out of 5 states in the urban category that were ranked the lowest in telehealth utilization did not have an in-state NCI designated cancer center. Conclusions: Telehealth services can bridge gaps in access to specialty cancer care for patients that do not live in geographic proximity of cancer centers. However, regions lacking geographic proximity to cancer centers were also regions with poorest telehealth utilization. Advocacy and policy efforts directed towards increasing access to telehealth can ensure equitable and timely access to specialized cancer care in these regions of need.
Thrombosis in multiple myeloma: Risk estimation by induction regimen and association with overall survival
Abstract Lenalidomide‐containing (R) triplet and quadruplet regimens are the standard of care for multiple myeloma (MM) and have been shown to increase the risk of thrombosis. The association between thromboembolism (TE) and survival in the novel multidrug era is not yet delineated. In this study, we evaluated the incidence of TE during the first year of MM diagnosis, its association with the type of induction regimen, and its impact on overall survival. We studied 672 newly diagnosed MM (NDMM) patients who received a triplet or quadruplet lenalidomide‐based induction at the Mayo Clinic, Rochester. TE was diagnosed in 83 patients (12.4%). Of these, 56 (8.3%) had a deep venous thrombosis (DVT), 23 (3.4%) had a pulmonary embolism (PE) with or without the DVT, and 4 (0.6%) patients had a stroke. Carfilzomib‐Rd (KRd) had the highest risk of TE (21.1%, 18/85), followed by quadruplets (11.1%, 5/45), bortezomib‐Rd (9.6%, 51/531), and 0/11 (0%), treated with other lenalidomide‐containing regimens. The difference in TE risk between KRd and the other regimens was statistically significant (OR = 2.6, p < .01). Nine patients developed a TE before being exposed to any treatment. Survival was significantly lower among patients that developed a TE (66 vs. 133 months, p < .01). The association of TE with reduced survival demonstrated in univariate analysis (HR = 2.2, 95% CI = 1.6–3.3) was maintained in the multivariable analysis adjusted for high‐risk interphase fluorescence in situ hybridization (FISH), sex, age, receipt of an upfront transplant, the response at induction, and the International Staging System (ISS) (HR = 2.61, CI = 1.74–3.9). We conclude that TE is an important aspect of MM management, and effective management is especially relevant in the novel treatment era.
Outcomes of Multiple Myeloma Patients Refractory to Standard Dose Vs Low Dose Lenalidomide
Abstract Multiple myeloma (MM) is a plasma cell malignancy that is characterized by diverse clinical presentations. Although biochemical assessment of disease activity is commonly used to monitor treatment response, findings on magnetic resonance imaging and positron emission tomography (PET)/computed tomography (CT), among other imaging modalities, have proven to harbor prognostic value. We sought to corroborate these findings by examining the prognostic significance of fluorodeoxyglucose PET/CT scanning in the setting of newly diagnosed MM. We retrospectively analyzed 195 patients with a PET/CT available at diagnosis and at 6 months posttreatment to examine their value as an adjuvant metric to conventional hematologic responses in terms of time to next treatment (TTNT) and overall survival (OS). The median TTNT and OS for the entire cohort were 24.6 months (95% confidence interval [CI], 20.4-29.1) and 79 months (95% CI, 63.1-119.1), respectively. When comparing PET/CT negative (−) with PET/CT positive (+) patients, we found significantly prolonged median TTNT (55.2 vs 17.8 months, P < .0001) and OS (unreached vs 60.8 months, P < .0001) in the former group. We then examined the additive value of PET/CT on the hematologic response achieved at 6 months and found that PET/CT (−) is associated with significantly increased median TTNT and OS for the very good partial response (VGPR) group and the less than VGPR group. Importantly, PET/CT retained prognostic significance after adjusting for multiple other predictive variables. We conclude that a PET/CT (−) at 6 months confers a significant prognostic advantage for patients with newly diagnosed MM and adds significant value to the hematologic response assessment.
Current approaches to management of newly diagnosed multiple myeloma
AbstractMajor developments in the treatment of multiple myeloma (MM) over the past decade have led to a continued improvement in survival. Significant progress has been made with deeper and longer remissions seen with newer treatment approaches—both for induction as well as maintenance therapy. The treatment approach to MM is guided by several factors including patient age, frailty, comorbidities, eligibility for autologous stem cell transplantation (ASCT), and risk stratification into standard‐risk or high‐risk MM. High‐risk MM is defined by the presence of t(4;14), t(14;16), t(14;20), del (17p), TP53 mutation, or gain (1q). Transplant eligible patients should receive 4–6 cycles of induction followed by stem cell collection. Patients can then undergo ASCT, or continue induction therapy and shift to maintenance, delaying ASCT till first relapse. Transplant ineligible patients should receive induction therapy followed by maintenance. For induction therapy prior to ASCT, a proteasome inhibitor‐IMiD combination remains standard with monoclonal antibody‐based quadruplets preferred in high‐risk patients. Among transplant ineligible patients, those with standard‐risk MM should receive DRd continued until disease progression, while bortezomib containing regimens (VRd or VRd lite) can be considered for high‐risk patients. Finally, standard‐risk patients should receive lenalidomide maintenance after induction/ASCT, while proteasome inhibitor‐IMiD combinations should be used for high‐risk patients.