Abstract: We analysed the prevalence of M184V/I and/or K65R/E/N mutations archived in proviral DNA (pDNA) in youths with perinatal HIV, virological control and who previously carried these resistance mutations in historic plasma samples. Methods We included vertically HIV-infected youths/young adults aged ≥10 years in the Madrid Cohort of HIV-1 Infected Children and Adolescents, exposed to lamivudine and/or emtricitabine, with M184V/I and/or K65R/E/N in historic plasma samples, on antiretroviral therapy (ART), virologically suppressed (HIV-1 RNA & lt;50 copies/mL), and with available PBMCs in the Spanish HIV BioBank. Genomic DNA was extracted from PBMCs and HIV-1 RT gene was amplified and sequenced for resistance testing by Stanford HIV Resistance tool. Results Among the 225 patients under follow-up in the study cohort, 13 (5.8%) met selection criteria, and RT sequences were recovered in 12 (92.3%) of them. All but one were Spaniards, carrying subtype B, with a median age at PBMCs sampling of 21.3 years (IQR: 15.6–23.1) with 4 years (IQR 2.1–6.5) of suppressed viral load (VL). Nine (75%) youths did not present M184V/I in pDNA after at least 1 year of viral suppression. In December 2019, the remaining three subjects carrying M184V/I in pDNA maintained suppressed viraemia, and two still used emtricitabine in ART. Conclusions The prevalence of resistance mutations to lamivudine and emtricitabine in pDNA in a cohort of youths perinatally infected with HIV who remain with undetectable VL, previously lamivudine and/or emtricitabine experienced, was infrequent. Our results indicate that ART including lamivudine or emtricitabine may also be safe and successful in youths with perinatal HIV with previous experience of and resistances to these drugs detected in plasma.

Abstract: The aim of this transversal study was to describe the virological and immunological features of HIV-infected youths transferred from pediatric to adult care units since 1997 vs. the non-transferred patients from the Madrid Cohort of HIV-infected children and adolescents in Spain. We included 106 non-transferred and 184 transferred patients under clinical follow-up in 17 public hospitals in Madrid by the end of December 2017. Virological and immunological outcomes were compared in transferred vs. non-transferred patients. ART drug resistance mutations and HIV-variants were analyzed in all subjects with available resistance pol genotypes and/or genotypic resistance profiles. Among the study cohort, 133 (72.3%) of 184 transferred and 75 (70.7%) of 106 non-transferred patients had available resistance genotypes. Most (88.9%) of transferred had ART experience at sampling. A third (33.3%) had had a triple-class experience. Acquired drug resistance (ADR) prevalence was significantly higher in pretreated transferred than non-transferred patients (71.8% vs. 44%; p = 0.0009), mainly to NRTI (72.8% vs. 31.1%; p  〈  0.0001) and PI (29.1% vs. 12%; p = 0.0262). HIV-1 non-B variants were less frequent in transferred vs. non-transferred (6.9% vs. 32%; p  〈  0.0001). In conclusion, the frequent resistant genotypes found in transferred youths justifies the reinforcement of HIV resistance monitoring after the transition to avoid future therapeutic failures.

Abstract: Although integrase inhibitor (INI)-based regimens are now the first-line choice for all people living with HIV, experience among children and adolescents is still scarce. We describe the characteristics and outcomes of a paediatric/adolescent cohort on INI-based ART. Methods Retrospective analysis of HIV-infected patients below 18 years of age who started an INI-based regimen from 2007 to 2019, enrolled in the Spanish National Adult (CoRIS) and Paediatric (CoRISpe) cohorts. Resistance mutations were identified by the Stanford HIV Drug Resistance Database. Results Overall, 318 INI-based regimens were implemented in 288 patients [53.8% female; median age at start of 14.3 years (IQR 12.0–16.3)]. Most were born in Spain (69.1%), vertically infected (87.7%) and treatment-experienced (92.7%). The most frequently prescribed INI was dolutegravir (134; 42.1%), followed by raltegravir (110; 34.6%) and elvitegravir (73; 23.0%). The median exposure was 2.0 years (IQR 1.1–3.0). The main reasons to start an INI-based therapy were treatment simplification (54.4%) and virological failure (34.3%). In total, 103 (32.4%) patients interrupted their regimen: 14.5% for simplification and 8.5% due to virological failure. Most subjects who received dolutegravir (85.8%) and elvitegravir (83.6%) did not interrupt their regimen and maintained undetectable viral load. There were only five virological failures with dolutegravir and three with elvitegravir. There were no interruptions related to adverse events. Seven patients with virological failure presented major resistance mutations to INIs; none of them were on dolutegravir. Conclusions INI-based regimens were effective and safe for HIV treatment in children and adolescents. Dolutegravir and elvitegravir presented an excellent profile, and most patients achieved and maintained viral suppression.

Abstract: INTRODUCTION: High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard treatment for patients with relapsed or refractory aggressive B-cell lymphoma, and is frequently used as part of first-line therapy in patients with peripheral T-cell lymphoma (PTCL). However, long-term remission rates with this strategy are inferior to 50%, so novel approaches are required. We have designed a prospective multicenter phase II study to evaluate the safety and efficacy of bendamustine as part of conditioning regimen in patients with aggressive lymphomas undergoing ASCT. METHODS: Inclusion criteria were: histologic diagnosis of i) relapsed or refractory diffuse large B-cell lymphoma (DLBCL) or grade 3B follicular lymphoma (FL) in partial response (PR) or complete remission (CR) after salvage therapy, or ii) transformed DLBCL or peripheral T-cell lymphoma (PTCL) in first or subsequent PR or CR. Conditioning regimen consisted of bendamustine (200 mg/m2, days -7 and -6), etoposide (200 mg/m2, days -5 to -2), cytarabine (400 mg/m2, days -5 to -2), and melphalan (140 mg/m2, day -1) (BendaEAM regimen). Primary endpoint was progression-free survival (PFS) at 3 years. Secondary endpoints were toxicity, response to transplant at 3 months, and overall survival (OS). This trial was registered at EMEA (EUDRACT number 2010-020926-17). RESULTS: Sixty patients (median age 54 years, range 27-70) from 22 Spanish hospitals were included since May 2011 to November 2012. Histologies were: 40 DLBCL, 3 grade 3B FL, 13 transformed DLBCL, and 7 PTCL. 82% of patients have received ³2 lines of treatment prior to ASCT. 37 patients (62%) were in CR at the time of transplant and 23 (38%) in PR. A median number of 4.05 x 106/Kg (range: 1.69-19.80) CD34+ cells were reinfused. All patients (except one who died early) engrafted after a median of 11 (range: 9 to 72) and 14 (range: 4 to 53) days, respectively, to achieve 〉 0.5 x109/L neutrophils and 〉 20 x109/L platelets. 39 serious adverse events (SAEs) were reported before day +100, including 14 infectious episodes, 2 of them resulting in respiratory failure and death (3.3% of transplant related mortality). Another major SAE was renal toxicity developed by 5 patients (8.3%) after bendamustine administration, reversible in all cases (3 of these patients had developed mild renal failure during previous salvage therapy). Non-relapse mortality after day +100 was 3.3% (1 patient died because of Wernicke's encephalopathy, and 1 patient from infectious complications). Concerning response to transplant, 44 patients (73.3%) achieved CR, 7 (11.7%) PR, and 6 patients (10%) did not respond. Univariate analysis showed that patients who received more than 2 lines of treatment prior to transplant (1 line: 100% of CR post-transplant; 2 lines: 71%; 〉 2 lines: 50%; p=0.013), and those who were in PR at transplant (48% vs 89%, p 〈 0.001) had lower CR rates after ASCT (day +100), although only disease status at transplant retained the significant influence in the multivariate analysis (RR: 0.11, 95% CI: 0.03-0.42, p=0.001). Histological diagnosis had no significant influence on CR rates after ASCT (DLBCL: 73%; transformed DLBCL: 69%; PTCL: 86%; p 〉 0.1). At the time of analysis, 13 patients (22%) had disease progression and 8 patients (13%) have died (4 from lymphoma, and 4 from other causes). With a median follow-up of 18.9 (9.5 to 32.3) months, the estimated 2-year PFS and OS were 73% and 88%, respectively. CONCLUSIONS: The BendaEAM conditioning regimen is feasible and active in patients with aggressive lymphomas. Toxicity profile is similar to that commonly observed in the ASCT setting, but renal toxicity can occur and should be carefully monitored, especially in patients with prior history of renal failure. Longer follow-up is needed to assess the long-term toxicity and the efficacy of this regimen, although patients who are not in CR before transplant seem to have poorer outcomes. Disclosures No relevant conflicts of interest to declare.

Abstract: Recent evidence suggests that the prognostic impact of gene mutations in patients with chronic lymphocytic leukemia (CLL) may differ depending on the immunoglobulin heavy variable (IGHV) gene somatic hypermutation (SHM) status. In this study, we assessed the impact of nine recurrently mutated genes ( BIRC3 , EGR2 , MYD88, NFKBIE , NOTCH1 , POT1 , SF3B1, TP53 , and XPO1 ) in pre-treatment samples from 4580 patients with CLL, using time-to-first-treatment (TTFT) as the primary end-point in relation to IGHV gene SHM status. Mutations were detected in 1588 (34.7%) patients at frequencies ranging from 2.3–9.8% with mutations in NOTCH1 being the most frequent. In both univariate and multivariate analyses, mutations in all genes except MYD88 were associated with a significantly shorter TTFT. In multivariate analysis of Binet stage A patients, performed separately for IGHV-mutated (M-CLL) and unmutated CLL (U-CLL), a different spectrum of gene alterations independently predicted short TTFT within the two subgroups. While SF3B1 and XPO1 mutations were independent prognostic variables in both U-CLL and M-CLL, TP53 , BIRC3 and EGR2 aberrations were significant predictors only in U-CLL, and NOTCH1 and NFKBIE only in M-CLL. Our findings underscore the need for a compartmentalized approach to identify high-risk patients, particularly among M-CLL patients, with potential implications for stratified management.

Abstract: The mutational status of the immunoglobuin heavy variable (IGHV) genes is an undisputable strong prognostic factor that subdivides patients with chronic lymphocytic leukemia (CLL) into 2 subgroups, i.e. IGHV-unmutated CLL (U-CLL) and IGHV-mutated CLL (M-CLL). U-CLL and M-CLL have distinct landscapes of genomic aberrations as well as distinct prognosis, since U-CLL is considerably more aggressive than M-CLL. That said, there is considerable clinical heterogeneity among M-CLL patients, ranging from patients without need of treatment to patients requiring early therapeutic intervention, indicating the need to further refine prognosis in this subgroup. In recent years, it has become evident that the prognostic impact of genomic aberrations may differ depending on IGHV gene mutational status. Hence, defining genomic aberrations with prognostic impact in M-CLL patients may help identifying patients with an predicted unfavorable prognosis within this subgroup, with obvious implications for management of follow up and therapy choice. To study the clinical impact of recurrent gene mutations in relation to IGHV gene mutational status, we collected a large, multi-center cohort including 4,674 patients with CLL [median age at diagnosis, 64.5 years; male/female, n=2,962 (63%)/n=1,712 (37%); Binet stage A (n=3,369, 74%), B (n=827, 18%), and C (n=387, 8%); IGHV-mutated (M-CLL, n=2,498, 56%) and IGHV-unmutated (U-CLL, n=1,927, 44%); isolated del(13q) (n=1,868, 41%), trisomy 12 (n=571, 13%), del(11q) (n=503, 11%), and del(17p) (n=249, 5.5%); treated (n=2,745, 59%) and untreated (n=1,929, 41%)] and performed next-generation sequencing (NGS) and/or Sanger sequencing of 9 genes (BIRC3, EGR2, NFKBIE, MYD88, NOTCH1, POT1, SF3B1, TP53, and XPO1) on pre-treatment samples. Overall, pathogenic mutations in any of these genes were detected in 1720/4674 patients (36.8%, using a variant allele frequency cutoff of 5% for NGS), while the remaining patients were wildtype; 2 mutations were observed in 361 patients (7.7%) and 3 or more mutations in 58 patients (1.2%). The mutation frequency for the individual genes was: TP53 (10.4%, including TP53 mutations and/or del(17p)), NOTCH1 (10.1%, 3'UTR mutations not included), SF3B1 (9.3%), XPO1 (3.9%), POT1 (3.8%), NFKBIE (3.7%), BIRC3 (3.0%), EGR2 (2.5%) and MYD88 (2.5%; Figure 1A). Except for MYD88, gene mutations in each of the investigated genes were associated with significantly shorter time-to-first-treatment (TTFT) in univariate analysis. In multivariate analysis of Binet stage A patients (n=3,369; including all genes, IGHV gene mutational status, age at diagnosis and gender), SF3B1 (Hazard Ratio (HR) 1.79; p & lt;0.001) , BIRC3 mutations (HR 1.50; p=0.004), XPO1 (HR 1.29; p=0.020), EGR2 (HR 1.42; p=0.021) and TP53 aberrations (HR 1.21; p=0.028), along with unmutated IGHV genes (HR 4.21; p & lt;0.001) and male gender (HR 1.12; p=0.027) remained as independent factors for shorter TTFT. In a multivariate model focusing on M-CLL Binet stage A patients (n=2,049), SF3B1 (HR 2.72; p & lt;0.001), NOTCH1 (HR 1.65; p=0.006), XPO1 (HR 2.21; p=0.021) and NFKBIE mutations (HR 1.74; p=0.025) were independent markers of poor TTFT (Figure 1B), while conversely in U-CLL Binet stage A cases (n=1157), SF3B1 mutations (HR 1.49; p & lt;0.001), TP53 aberrations (HR 1.30; p=0.011), BIRC3 mutations (HR 1.49; p=0.016) and male gender (HR 1.20; p=0.012) were significant factors for shorter TTFT (Figure 1C). In summary, different spectra of genetic mutations independently predicted short TTFT in M-CLL and U-CLL, respectively, with SF3B1 mutations as the only aberration found to be significant predictor of shorter time to first treatment in both subgroups. Importantly, mutations within several genes (i.e. SF3B1, NOTCH1, XPO1 and NFKBIE) identified patients in the M-CLL subgroup with a high-risk profile; conversely, TP53 mutations did not affect TTFT in this subgroup. On these grounds, we suggest to include analysis of recurrent gene mutations to identify high-risk patients within the M-CLL subgroup. Figure 1 Figure 1. Disclosures Brieghel: AstraZeneca: Consultancy. Rossi: Janssen: Honoraria, Research Funding; AstraZeneca: Honoraria, Research Funding; Gilead: Honoraria, Research Funding; Abbvie: Honoraria, Research Funding; Verastem: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Cellestia: Honoraria, Research Funding. Scarfo: Astra Zeneca: Honoraria; Abbvie: Honoraria; Janssen: Honoraria, Other: Travel grants. Mattsson: Gilead: Research Funding. Baliakas: Janssen: Honoraria; Gilead: Honoraria, Research Funding; Abbvie: Honoraria. Martinez-Lopez: Janssen: 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; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: 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; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees. de la Serna: AbbVie, AstraZeneca, Beigene, Gilead, GSK, Janssen, Jazzpharma, Novartis, Roche: Consultancy; ABBVIE, ASTRAZENECA,ROCHE: Research Funding; AbbVie, AstraZeneca, Roche: Speakers Bureau. Hernández Rivas: Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene/BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees. Smedby: Jansen-Cilag: Other: part of a research collaboration between Karolinska Institutet and Janssen Pharmaceutica NV for which Karolinska Institutet has received grant support. Bullinger: Pfizer: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Gilead: Consultancy; Daiichi Sankyo: Consultancy, Honoraria; Hexal: Consultancy; Janssen: Consultancy, Honoraria; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding; Menarini: Consultancy; Novartis: Consultancy, Honoraria; Amgen: Honoraria; Astellas: Honoraria; Sanofi: Honoraria; Seattle Genetics: Honoraria; Bayer: Research Funding. Bosch: TAKEDA: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel; AbbVie: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel. Terol: BMS: Consultancy; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel; Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; Roche: Consultancy; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Travel; Hospital Clinico Valencia: Current Employment. Cuneo: AstraZeneca: Consultancy, Speakers Bureau; Janssen: Consultancy, Speakers Bureau; Gilead: Consultancy, Speakers Bureau; AbbVie: Consultancy, Speakers Bureau. Gaidano: Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Incyte: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees; Astrazeneca: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Niemann: Novo Nordisk Foundation: Research Funding; CSL Behring, Genmab, Takeda, Octapharma: Consultancy; Abbvie, AstraZeneca, Janssen: Consultancy, Research Funding. Ghia: Roche: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Sunesis: Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Acerta/AstraZeneca: Consultancy, Honoraria, Research Funding; AstraZeneca: Consultancy, Honoraria, Research Funding; ArQule/MSD: Consultancy, Honoraria; BeiGene: Consultancy, Honoraria; Celgene/Juno/BMS: Consultancy, Honoraria; Gilead: Consultancy, Research Funding. Rosenquist: Roche: Honoraria; Janssen: Honoraria; Illumina: Honoraria; AstraZeneca: Honoraria; Abbvie: Honoraria.