Kurzfassung: Newly diagnosed multiple myeloma (NDMM) patients treated with immunomodulatory drugs are at high risk of venous thromboembolism (VTE), but data are lacking from large prospective cohorts. We present thrombosis outcome data from Myeloma IX (n = 1936) and Myeloma XI (n = 4358) phase 3 randomized controlled trials for NDMM that treated transplant-eligible and transplant-ineligible patients before and after publication of thrombosis prevention guidelines. In Myeloma IX, transplant-eligible patients randomly assigned to cyclophosphamide, vincristine, doxorubicin, and dexamethasone (CVAD) induction had higher risk of VTE compared with patients treated with cyclophosphamide, thalidomide, and dexamethasone (CTD) (22.5% [n = 121 of 538] vs 16.1% [n = 89 of 554] ; adjusted hazard ratio [aHR],1.46; 95% confidence interval [95% CI] , 1.11-1.93). For transplant-ineligible patients, those randomly assigned to attenuated CTD (CTDa) induction had a higher risk of VTE compared with those treated with melphalan and prednisolone (MP) (16.0% [n = 68 of 425] vs 4.1% [n = 17 of 419] ; aHR, 4.25; 95% CI, 2.50-7.20). In Myeloma XI, there was no difference in risk of VTE (12.2% [n = 124 of 1014] vs 13.2% [n = 133 of 1008] ; aHR, 0.92; 95% CI, 0.72-1.18) or arterial thrombosis (1.2% [n = 12 of 1014] vs 1.5% [n = 15 of 1008] ; aHR, 0.80; 95% CI, 0.37-1.70) between transplant-eligible pathways for patients treated with cyclophosphamide, lenalidomide, and dexamethasone (CRD) or CTD. For transplant-ineligible patients, there was no difference in VTEs between attenuated CRD (CRDa) and CTDa (10.4% [n = 95 of 916] vs 10.7% [n = 97 of 910]; aHR, 0.97; 95% CI, 0.73-1.29). However, arterial risk was higher with CRDa than with CTDa (3.1% [n = 28 of 916] vs 1.6% [n = 15 of 910]; aHR, 1.91; 95% CI, 1.02-3.57). Thrombotic events occurred almost entirely within 6 months of treatment initiation. Thrombosis was not associated with inferior progression-free survival (PFS) or overall survival (OS), apart from inferior OS for patients with arterial events (aHR, 1.53; 95% CI, 1.12-2.08) in Myeloma XI. The Myeloma XI trial protocol incorporated International Myeloma Working Group (IMWG) thrombosis prevention recommendations and compared with Myeloma IX, more patients received thromboprophylaxis (80.5% vs 22.3%) with lower rates of VTE for identical regimens (CTD, 13.2% vs 16.1%; CTDa, 10.7% vs 16.0%). However, thrombosis remained frequent in spite of IMWG-guided thromboprophylaxis, suggesting that new approaches are needed.

Kurzfassung: Introduction Bone marrow based minimal residual disease (MRD) assessments provide greater sensitivity for residual disease detection compared to the standard serological techniques and MRD negativity is associated with improved progression-free survival (PFS). However, the frequency at which MRD can be assessed is limited by the invasive nature and cost of the current assays. These assays may also give false negative results due to the heterogeneous nature of marrow involvement in multiple myeloma and extramedullary disease. Mass spectrometry (MS) methodologies are emerging as a more sensitive way of monitoring monoclonal proteins in the peripheral blood. In this study we assessed the prognostic impact of detectable residual monoclonal FLC by matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) MS in patients with transplant-eligible newly diagnosed multiple myeloma. Methods Patients treated with carfilzomib, lenalidomide, cyclophosphamide and dexamethasone followed by autologous stem cell transplantation (ASCT) and randomisation between lenalidomide maintenance versus observation in the Myeloma XI trial were included in this study. Patients with no residual serum for MS testing from baseline or post cycle one of induction chemotherapy were excluded as a baseline sample was required to establish the isotype and mass-to-charge ratio of the monoclonal FLC. 293 patients were included in this study: 58.4% (171/293) had an IgG monoclonal protein; 23.9% (70/293) had an IgA monoclonal protein;16.4% (48/293) had a FLC only monoclonal protein; 1.0% (3/293) had an IgD monoclonal protein and 0.3% (1/293) had non-secretory myeloma. MS analysis was performed on all available samples from post-induction (n=219), day+100 post ASCT (n=189) and post maintenance randomisation (n=137). Serum samples underwent immunoprecipitation with antisera specific for kappa and lambda FLC conjugated to magnetic microparticles, FLC were eluted and the spectra were acquired by MALDI-TOF MS. Progression free survival (PFS) analysis was performed with SPSS 27.0.1.0 using the Kaplan-Meier method. The log-rank test was used to assess the statistical significance of differences between survival curves. Median follow-up was calculated using the reverse Kaplan-Meier method. Results At all three time points MS positivity was associated with shorter PFS: 43.9 months v. not reached (NR) p & lt;0.001 post induction; 45.3 months v. NR p & lt;0.001 at day+100 post ASCT; and 44.1 months v. NR p & lt;0.001 post maintenance randomisation. Post induction 91/219 (41.6%) patients were in CR/sCR and 31/91 (34.1%) had residual monoclonal FLC detectable by MS. Patients in CR/sCR with residual monoclonal FLC detectable by MS post induction had a trend towards shorter PFS compared to MS negative patients (51.1 months v. not reached, p=0.097). At day+100 post ASCT 113/189 (59.8%) were in CR/sCR and 30/113 (26.5%) had residual monoclonal FLC detectable by MS. After a median follow-up of 46.9 months, MS negativity was associated with improved PFS in patients in CR/sCR (p=0.027); 12/30 (40%) MS positive patients have progressed versus 18/83 (21.7%) MS negative patients. Post maintenance randomisation 75/137 (54.7%) of patients were in CR/sCR and 12/75 of these patients (16%) were positive by MS. MS positive patients in CR/sCR had a shorter PFS compared to MS negative patients in CR/sCR (47.1 months v NR, p=0.017). 47 patients had bone marrow MRD (8 colour panel with a sensitivity of 4 x 10 -5) results from post maintenance randomisation: 35 (74.5%) were MRD negative and 12 (25.5%) were MRD positive. 6/35 (17.1%) patients who were MRD negative had residual monoclonal FLC detectable by MS. After a median follow-up of 42.2 months MS positivity in MRD negative patients was associated with shorter PFS; 2/6 (33.3%) MRD negative MS positive patients had progressed versus 2/29 (6.9%) MRD negative MS negative patients (p=0.001). The relapses in the MS positive patients occurred earlier (at 18.8 and 31.0 months) than those observed in the double negative patients (at 43.8 and 51.3 months). Conclusions MS provided additional sensitivity for residual disease detection in patients in CR and positivity was associated with reduced PFS. MS also added additional prognostic information for patients who were MRD negative during maintenance with residual positivity being associated with an increased risk of early relapse. Disclosures Giles: The Binding Site: Research Funding. Drayson: Abingdon Health: Current holder of individual stocks in a privately-held company. Wright: The Binding Site: Current Employment. Cook: Pfizer: Consultancy, Honoraria; Oncopeptides: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Roche: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding. Morgan: BMS: Membership on an entity's Board of Directors or advisory committees; Jansen: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees. Cairns: Takeda: Research Funding; Amgen: Research Funding; Merck Sharpe and Dohme: Research Funding; Celgene / BMS: Other: travel support, Research Funding. Menzies: Celgene / BMS: Research Funding; Amgen: Research Funding; Merck Sharpe and Dohme: Research Funding. Kaiser: AbbVie: Consultancy; Janssen: Consultancy, Other: Educational support, Research Funding; Karyopharm: Consultancy, Research Funding; Pfizer: Consultancy; Amgen: Honoraria; Seattle Genetics: Consultancy; Takeda: Consultancy, Other: Educational support; GSK: Consultancy; BMS/Celgene: Consultancy, Other: Travel support, Research Funding. Pawlyn: Amgen: Honoraria; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene / BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees. Jackson: oncopeptides: Consultancy; celgene BMS: Consultancy, Honoraria, Research Funding, Speakers Bureau; amgen: Consultancy, Honoraria, Speakers Bureau; takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; GSK: Consultancy, Honoraria, Speakers Bureau; J and J: Consultancy, Honoraria, Speakers Bureau; Sanofi: Honoraria, Speakers Bureau. Pratt: Janssen: Consultancy; Gilead: Consultancy; Binding Site: Consultancy; Amgen: Consultancy; Takeda: Consultancy; BMS/Celgene: Consultancy.

Kurzfassung: Multiple myeloma (MM) is a disease characterized by the abnormal proliferation of plasma cells in the bone marrow. We and others have recently demonstrated the existence of different myeloma subclones phylogenetically related to the founding clone. This intra-clonal heterogeneity is the basis for disease progression, treatment resistance, and relapse. However, the clinical and biological relevance of the presence and diversity of different myeloma subclones has not been fully established. In this study, we used whole exome sequencing (WES) plus a pull down of the MYC, IGH, IGL and IGK loci as a tool to analyze the largest series of presenting cases of myeloma (463 patients) to date, which were entered into the Myeloma XI trial (NCT01554852). DNA from both tumor and peripheral blood samples were used in the exome capture protocol following the SureSelect Target Enrichment System for Illumina Paired-End Sequencing Library v1.5. Exome reads were used to call single nucleotide variants (SNVs), indels, translocations, and copy number aberrations. The proportion of tumor cells containing an SNV was inferred. The presence and proportion of subclones were defined in a subset of 437 patients using a genetic algorithm based-tool (GAUCHO), which also calculated different indices of clonal diversity: number of clones, mean pairwise genetic divergence, Shannon and Inverse Simpson diversity index and Berger-Parker dominance index. Based on these results, we aimed to determine the clinical implications of the number of mutations and the subclonal diversity of MM at presentation in progression free (PFS) and overall survival (OS). We found that MM patients with t(14;16) and t(14;20) had more exonic mutations (not including Ig variants) than the rest of samples (median 87 versus 43, p 〈 0.001). Additionally, we found that MM patients with an APOBEC signature or with mutations in ATM/ATR had significantly more mutations than patients without these genetic lesions with a median number of 137 mutations (range 20-569) and 84.5 (range 33-319) respectively (p 〈 0.001). Subsequently, we identified patients with high number of mutations ( 〉 59 mutations) that had a worse outcome in terms of OS (2-year OS rate of 71% (95% CI, 63-80%) vs. 82% (95% CI, 78-87%), p=0.02), but not progression free survival (median 22.5 (95% CI 18.7-30.2) vs. 27.5 (95% CI, 25.8-30.5) months, p=0.1) We reported recurrent mutated genes in myeloma with mutations being present at both clonal and subclonal levels (IRF4, RB1, DIS3, BRAF, KRAS, and NRAS), whereas other genes were mutated only at clonal (HIST1H1E, LTB, TP53 or EGR1), or subclonal levels (CYLD, TRAF3, MAX). These results give insights about the differences in mutation acquisition times and potential subclonal fitness. We inferred that the median number of clones present in this myeloma series was 5, and determined the prognostic value of the number and diversity of subclones in MM patients. The prognostic impact of having high number of clones was unclear as no significant differences were found. On the contrary, there was a significant difference in terms of outcome when calculating distinct measurements of subclonal diversity. Briefly, MM patients with high values of inverse Simpson diversity index had a significantly poorer PFS (median 13.2 (95% CI, 9.4-∞) vs. 26.9 months (95% CI, 24-30.2) months, p=0.02) and OS (66% (95% CI, 52-82%) vs. 81% (95% CI, 77-85%) alive at 2-years, p=0.01); and, alternatively, MM patients who did not have a dominant subclone accounting for 〉 25% of MM cells (low values of Berger-Parker Dominance index, n=56) had a significantly shorter PFS than those with a dominant clone accounting for more than 25% of cells with a median of 22 (95% CI, 12.3-26.3) vs. 27.5 months (95% CI, 23.9-30.9) respectively, p=0.02. Our results show that mutational load and subclonal diversity are poor prognostic factors in myeloma. Previous studies from massive-parallel sequencing and single cell analyses of myeloma plasma cells already revealed that myeloma had the features of an evolutionary ecosystem, where different tumour subclones coexist and have differential response to treatment. We have demonstrated in this study that measures of tumor diversity have important clinical consequences. To our knowledge, this is the first time that the use of clonal diversity indices as predictive biomarkers of progression is proposed in haematological malignancies, and more specifically, myeloma. Disclosures Walker: Onyx Pharmaceuticals: Consultancy, Honoraria.

Kurzfassung: Introduction Identifying molecular high risk myeloma remains a diagnostic challenge. We previously reported co-segregation of 〉 1 adverse lesion [t(4;14), t(14;16), t(14;20), gain(1q), del(17p)] by iFISH to specifically characterise a group of high risk patients (Boyd et al., Leukemia 2012). However, implementation of this approach is difficult using FISH because of its technical limitations. We recently developed and validated a novel high-throughput all-molecular testing strategy against FISH (MyMaP- Myeloma MLPA and translocation PCR; Kaiser MF et al., Leukemia 2013; Boyle EM et al., Gen Chrom Canc 2015). Here, we molecularly characterised 1,036 patients from the NCRI Myeloma XI trial using MyMaP and validated the co-segregation approach. Materials, Methods and Patients Recurrent translocations and copy number changes were assayed for 1,036 patients enrolled in the NCRI Myeloma XI (NCT01554852) trial using CD138+ selected bone marrow myeloma cells taken at diagnosis. The trial included an intensive therapy arm for younger and fitter and a non-intense treatment arm for elderly and frail patients. Analysis was performed using MyMaP, which comprises TC-classification based multiplex qRT-PCR and multiplex ligation-dependent probe amplification (MLPA; MRC Holland). Median follow up for the analysis was 24 months. Results Adverse translocations [t(4;14), t(14;16), t(14;20)] were present in 18.2% of cases, del(17p) in 9.3%, gain(1q) in 34.5% and del(1p32) in 9.4% of cases. All adverse lesions were associated with significantly shorter PFS and OS by univariate analysis (P 〈 0.05 for all). Of the 1,036 analysed cases, 13.5% carried 〉 1 adverse lesion, 33.9% had one isolated adverse lesion and 52.6% had no adverse lesion. Presence of 〉 1, 1 or no adverse lesion was associated with a median PFS of 17.0, 23.9 and 30.6 months (P =3.0x10-9) and OS at 24 months of 67.9%, 75.0% and 86.0% (P =1.8x10-7), respectively. Del(1p) was associated with shorter PFS and OS for the intensive, but not for the non-intensive therapy arm and was independent of the co-segregation model by multivariate analysis regarding OS (P =0.006). We thus included del(1p) as an additional adverse lesion in the model for younger patients. The groups with 〉 1 (19.4% of cases), 1 (31.1%) and no adverse lesions (49.5%) were characterised by median PFS of 19.4, 29.4 and 39.1 months (P =1.2x10-10) and median 24-months survival of 73.8%, 86.4% and 91.5% (P =1.4x10-6), respectively. Hazard Ratio for 〉 1 adverse lesion was 3.0 (95% CI 2.1-4.1) for PFS and 3.8 (95% CI 2.2-6.5) for OS. By multivariate analysis, co-segregation of adverse lesions was independent of ISS for PFS/OS in the entire group of 1,036 cases and in the intensive treatment arm. We integrated adverse lesions and ISS into a combined model defining High Risk ( 〉 1 adv les + ISS 2 or 3; 1 adv les + ISS 3) and Low Risk (no adv les + ISS 1 or 2; 1 adv les + ISS 1) and the remainder as Intermediate Risk. The High Risk, Intermediate Risk and Low Risk groups of the total cohort included 11.2%, 41.2% and 41.6% of cases with median PFS of 15.8, 19.8 and 35.2 months (P 〈 2.2x10-16) and median OS at 24 months of 62.9%, 73.7%, and 90.7% (P =4.0x10-14), respectively. Integration of ISS into the model for younger patients resulted in highly specific identification of a High Risk group (15.6% of cases) with HR 3.8 (CI 2.6-5.4) for PFS and 6.2 (CI 3.3-11.6) for OS. Conclusions Co-segregation analysis of adverse genetic lesions is a specific molecular risk stratification tool which has now been validated in two large independent trials including a real-world population of all age groups (UK MRC Myeloma IX; NCRI Myeloma XI; total 1,905 patients). MyMaP is a validated all-molecular analysis approach that makes the otherwise technically challenging assessment of multiple genetic regions by FISH accessible using standard laboratory equipment without bioinformatics requirements. Disclosures Kaiser: BristolMyerSquibb: Consultancy; Chugai: Consultancy; Janssen: Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria. Pawlyn:Celgene: Honoraria, Other: Travel support; The Institute of Cancer Research: Employment. Jones:Celgene: Other: Travel support, Research Funding. Savola:MRC Holland: Employment. Owen:Celgene: Honoraria, Research Funding; Janssen: Honoraria. Cook:Celgene: Consultancy, Research Funding, Speakers Bureau; BMS: Consultancy; Sanofi: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Takeda Oncology: Consultancy, Research Funding, Speakers Bureau; Janssen: Consultancy, Research Funding, Speakers Bureau. Gregory:Celgene: Honoraria; Janssen: Honoraria. Davies:Takeda-Milenium: Honoraria; Onyx-Amgen: Honoraria; Celgene: Honoraria; University of Arkansas for Medical Sciences: Employment. Jackson:Celgene: Honoraria; Takeda: Honoraria; Amgen: Honoraria. Morgan:Weisman Institute: Honoraria; Takeda-Millennium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; University of Arkansas for Medical Sciences: Employment; CancerNet: Honoraria; MMRF: Honoraria.

Kurzfassung: Introduction New drugs have significantly improved the outcome of MM patients (pts) increasing both progression free survival (PFS) and overall survival (OS). Among new drugs lenalidomide (LEN) due to its oral availability and favourable toxicity profile is an attractive option both as an induction and as a maintenance treatment, with different studies demonstrating its effectiveness. Long term therapy with LEN, however, has been associated with an increased risk of developing SPMs. Aims We are conducting a large phase III study to evaluate the use of LEN as induction and/or as maintenance therapy. The primary end points of the study are OS and PFS. Secondary end points are response and toxicity. Methods Pts are treated following an intensive or a non intensive pathway based on their eligibility for high dose Melphalan (HDM) and stem cell transplantation (ASCT) and are randomised to receive induction therapy with cyclophosphamide and dexamethasone combined with either LEN (CRD) or thalidomide (CTD). Pts failing to achieve an optimal response are randomised to receive additional therapy with cyclophosphamide, dexamethasone and bortezomib (CVD) or no extra therapy. Pts with minimal or no response will automatically receive further therapy with CVD. A randomisation between LEN maintenance and no maintenance is also performed. Data on the occurrence of SPMs are being routinely collected as part of safety assessment during all protocol phases and follow up. Analyses were performed on treatment actually received. Results As per cut off of the 23rd July, 2371 pts have undergone the induction randomisation, of which 2368 are eligible for the safety analysis; 794 pts entered maintenance randomisation. The median follow up is 1.36 years from initiation of the study and 1.06 years from maintenance randomisation. Localised skin cancer other than melanoma were considered as non-invasive SPMs. At the time of the present analysis 17 SPMs have been reported with a cumulative incidence rate of 0.7% (cumulative rate of 0.6% for invasive SPMs and 0.1% for non-invasive SPMs); four additional patients, reported as having a SPM, were excluded, after central review of the data, either due to a previous history of malignancy or because of the evidence of a pre-existing tumour other than MM at the time of study entry. The median age at the time of SPMs development is 72 years (range 61-92), and the median time from trial entry to development of SPMs is 11 months (range 2.1-27.0). The most common SPMs reported were squamous cell carcinoma (4 pts, 2 invasive and 2 non invasive), breast cancer (3 pts), colon cancer (2 pts) and prostate cancer (2 pts). No haematological SPM has so far been reported. One patient, treated according to the intensive arm with LEN both as induction and maintenance, was reported as having a suspect myelodysplasia (MDS) due to anaemia and thrombocytopenia 2.7 months after entering the maintenance randomisation. No clear histological sign of MDS was found and the values improved after stopping maintenance treatment; these data fit with treatment related toxicity and not with the development of a MDS, and the patient was excluded from this analysis. Ten out of 17 SPMs developed during maintenance treatment or follow up phase, with 7 patients having received LEN maintenance. Median time from maintenance randomisation to SPMs development is 7 months (range 2-20.6 months). The remaining 7 were diagnosed during or immediately after induction. About half of the patients (8/17) were randomised to receive LEN induction; 3 patients received LEN both as induction and as maintenance. Interestingly only one of those 3 pts had been treated according to the intensive arm. With a median follow up of 1.36 years the estimated incidence rate at 1 and 2 years are 0.70% (95% CI .40-1.22)and 1.17% (95% CI .70-1.96) respectively (Figure 1). Conclusions Our data do not confirm previous findings of an excess risk of SPMs in association with the use of LEN and HDM in presenting patients, with 12/17 pts developing SPMs treated on the non intensive pathway that does not contain HDM. Most importantly only 0.4% of the patients enrolled within the intensive pathway developed a SPM, with only 2 of them receiving LEN maintenance. Longer follow up will help to further elucidate the risk of LEN associated SPMs. On behalf of the NCRI Haemato-Oncology subgroup Disclosures: Brioli: Celgene: Honoraria. Off Label Use: The presentation include the use of Lenalidomide as induction and as maintenance treatment for newly diagnosed multiple myeloma patients. Cook:Janssen: Honoraria, Research Funding, Speakers Bureau. Cavo:Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Millenium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Onyx: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Bristol-Meyer Squibb: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees. Morgan:Celgene: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Millenium: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Novartis: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Merck: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees; Johnson and Johnson: Consultancy, Honoraria, Membership on an entity’s Board of Directors or advisory committees.

Kurzfassung: Second‐generation immunomodulatory agents, such as lenalidomide, have a more favourable side‐effect profile than the first‐generation thalidomide, but their optimum combination and duration for patients with newly diagnosed transplant‐ineligible myeloma (ND‐TNE‐MM) has not been defined. The most appropriate delivery and dosing regimens of these therapies for patients at advanced age and frailty status is also unclear. The Myeloma XI study compared cyclophosphamide, thalidomide and dexamethasone (CTDa) to cyclophosphamide, lenalidomide and dexamethasone (CRDa) as induction therapy, followed by a maintenance randomisation between ongoing therapy with lenalidomide or observation for patients with ND‐TNE‐MM. CRDa deepened response but did not improve progression‐free (PFS) or overall survival (OS) compared to CTDa. However, analysis by age group highlighted significant differences in tolerability in older, frailer patients that may have limited treatment delivery and impacted outcome. Deeper responses and PFS and OS benefits with CRDa over CTDs were seen in patients aged ≤70 years, with an increase in toxicity and discontinuation observed in older patients. Our results highlight the importance of considering age and frailty in the approach to therapy for patients with ND‐TNE‐MM, highlighting the need for prospective validation of frailty adapted therapy approaches, which may improve outcomes by tailoring treatment to the individual.

Kurzfassung: Lenalidomide is an effective maintenance agent for patients with myeloma, prolonging first remission and, in transplant eligible patients, improving overall survival (OS) compared to observation. The ‘Myeloma XI’ trial, for newly diagnosed patients, aimed to evaluate whether the addition of the histone deacetylase inhibitor vorinostat to the lenalidomide maintenance backbone could improve outcomes further. Patients included in this analysis were randomised to maintenance therapy with lenalidomide alone (10 mg/day on days 1–21 of each 28‐day cycle), or in combination with vorinostat (300 mg/day on day 1–7 and 15–21 of each 28‐day cycle) with treatment continuing until unacceptable toxicity or progressive disease. There was no significant difference in median progression‐free survival between those receiving lenalidomide‐vorinostat or lenalidomide alone, 34 and 40 months respectively (hazard ratio [HR] 1.1 8, 95% confidence interval [CI] 0.96–1.44, p  = 0.109). There was also no significant difference in median OS, not estimable and 75 months respectively (HR 0.99, 95% CI 0.76–1.29, p  = 0.929). Subgroup analysis demonstrated no statistically significant heterogeneity in outcomes. Combination lenalidomide‐vorinostat appeared to be poorly tolerated with more dose modifications, fewer cycles of maintenance therapy delivered and higher rates of discontinuation due to toxicity than lenalidomide alone. The trial did not meet its primary end‐point, there was no benefit from the addition of vorinostat to lenalidomide maintenance.