BH3 profiling as pharmacodynamic biomarker for the activity of BH3 mimetics

Not available.

Response adaptive salvage with KTd and ASCT for functional high-risk multiple myeloma-The Australasian Leukemia and Lymphoma Group (ALLG) MM17 Trial

We evaluated re-induction incorporating carfilzomib-thalidomide-dexamethasone (KTd) and autologous stem cell transplantation (ASCT) for newly diagnosed multiple myeloma (NDMM) refractory, or demonstrating a suboptimal response, to non-IMID bortezomib-based induction. KTd salvage consisted of thalidomide 100 mg daily and dexamethasone 20 mg orally combined with carfilzomib 56 mg/m² days 1, 2, 8, 9, 15 and 16, of each 28-day cycle. Following four cycles, patients achieving a stringent complete response proceeded to ASCT whereas those who did not received a further two cycles then ASCT. Consolidation consisted of two cycles of KTd then Td to a total of 12 months post-ASCT therapy. Primary end-point was the overall response rate (ORR) with KTd prior to ASCT. Fifty patients were recruited. The ORR was 78% with EuroFlow MRD negativity of 34% in the intention-to-treat population and 65% in the evaluable population at 12 months post-ASCT. With follow-up >38 months median PFS and OS have not been reached with PFS and OS at 36 months of 64% and 80%, respectively. KTd was well tolerated with grade 3 and grade ≥4 adverse events rates of 32% and 10%, respectively. Response adaptive utilisation of KTd with ASCT is associated with both high-quality responses and durable disease control in functional high-risk NDMM.

Acquired mutations in BAX confer resistance to BH3-mimetic therapy in acute myeloid leukemia

Randomized trials in acute myeloid leukemia (AML) have demonstrated improved survival by the BCL-2 inhibitor venetoclax combined with azacitidine in older patients, and clinical trials are actively exploring the role of venetoclax in combination with intensive chemotherapy in fitter patients with AML. As most patients still develop recurrent disease, improved understanding of relapse mechanisms is needed. We find that 17% of patients relapsing after venetoclax-based therapy for AML have acquired inactivating missense or frameshift/nonsense mutations in the apoptosis effector gene BAX. In contrast, such variants were rare after genotoxic chemotherapy. BAX variants arose within either leukemic or preleukemic compartments, with multiple mutations observed in some patients. In vitro, AML cells with mutated BAX were competitively selected during prolonged exposure to BCL-2 antagonists. In model systems, AML cells rendered deficient for BAX, but not its close relative BAK, displayed resistance to BCL-2 targeting, whereas sensitivity to conventional chemotherapy was variable. Acquired mutations in BAX during venetoclax-based therapy represent a novel mechanism of resistance to BH3-mimetics and a potential barrier to the long-term efficacy of drugs targeting BCL-2 in AML.

Relationships Between Maternal Perinatal Mood, Sex of Infant, and Disappointment with Sex of Infant in a North American Sample

OBJECTIVES

Little is known about the relationships between sex of infant, disappointment with sex of infant, and risk for perinatal depression, particularly in societies where the nature of parental sex preference is thought to be "balanced" between male and female offspring. We sought to explore relationships between these variables in a North American population.

METHODS

In this exploratory study, we used data from a large Canadian prospective longitudinal study in which data were collected at up to four timepoints: during pregnancy, and at 1 week, 1 month and 3 months postpartum. Data about sex of infant, maternal preference for, and disappointment in sex of infant were recorded at the first possible timepoint; while at each postpartum timepoint infant fussiness and EPDS scores were recorded. We performed a mixed-effects linear regression to evaluate relationships between these variables.

RESULTS

In our sample of N = 207 women, EPDS scores were higher for mothers of male versus female infants, and independently associated with infant fussiness. There was no interaction between sex of infant and maternal disappointment, or between maternal disappointment and EPDS scores.

CONCLUSIONS

Mothers of male infants may have slightly more depressive symptoms than mothers of female infants regardless of maternal preference for, or disappointment in sex of infant; sex-specific biological risk factors for PPD should be explored.

Cancer Trial Impact: Understanding Implementation of the Short Course Oncology Treatment (SCOT) Trial Findings in colorectal cancer at a National Level

AIMS

The Short Course Oncology Treatment (SCOT) trial indicated that 3 months of adjuvant doublet chemotherapy was non-inferior to 6 months of treatment for patients with colorectal cancer, with considerably less toxicity. The SCOT trial results were disseminated in June 2017. The aim of this study was to understand if SCOT trial findings were implemented in Scotland.

MATERIALS AND METHODS

A retrospective analysis was carried out on a dataset derived from a source population of 5.4 million people. Eligible patients were those with stage II or III colorectal cancer who received adjuvant chemotherapy. Logistic regression was applied to understand the extent of practice change to a 3-month adjuvant chemotherapy duration after the SCOT trial results were disseminated. Interrupted time series analysis was used to visualise differences in prescribing trends before and after June 2017 for the overall cohort, and by SCOT trial eligibility.

RESULTS

In total, 2310 patients were included in the study; 1957 and 353 treated pre- and post-June 2017, respectively. The median treatment duration decreased from 21 weeks (interquartile range 14-24) prior to June 2017 to 12 weeks (interquartile range 12-21 weeks) after June 2017 (P < 0.001). The proportion of patients receiving over 3 months of adjuvant treatment decreased from 75% to 42% (P < 0.001). This change was most noticeable for patients who met the SCOT trial eligibility criteria, and specifically for those with low-risk stage III disease and those treated with capecitabine and oxaliplatin (CAPOX). Although practice change occurred in all locations, there were differences between regions that could be explained by pre-SCOT trial prescribing trends.

DISCUSSION

A significant change in chemotherapy prescribing occurred after dissemination of the SCOT trial results. National, real-world data can be used to capture the extent of implementation of clinical trial results. In this case, implementation was aligned with clinical trial subgroup findings. This type of analysis could be conducted to evaluate the impact of other clinical trials.

Phase I study of taminadenant (PBF509/NIR178), an adenosine 2A receptor antagonist, with or without spartalizumab, in patients with advanced non-small cell lung cancer

PURPOSE

The adenosine 2A receptor (A2AR) mediates the immunosuppressive effects of adenosine in the tumor microenvironment and is highly expressed in non-small cell lung cancer (NSCLC). Taminadenant (PBF509/NIR178) is an A2AR antagonist able to reactivate the antitumor immune response.

EXPERIMENTAL DESIGN

In this phase I/Ib, dose-escalation/expansion study, patients with advanced/metastatic NSCLC and {greater than or equal to}1 prior therapy received taminadenant (80-640 mg; orally; twice-daily) with or without spartalizumab (anti-programmed cell death-1; 400 mg; intravenously; every four weeks). Primary endpoints: safety, tolerability, and feasibility of the combination.

RESULTS

During dose escalation, 25 patients each received taminadenant alone or with spartalizumab; 19 (76.0%) and 9 (36.0%) had prior immunotherapy, respectively. Dose-limiting toxicities (all Grade 3) with taminadenant alone were alanine/aspartate aminotransferase increase and nausea (n=1 [4.0%] each; 640 mg) and in the combination group were pneumonitis (n=2 [8.0%]; 160 and 240 mg), fatigue and alanine/aspartate aminotransferase increase (n=1 [4.0%] each; 320 mg); pneumonitis cases responded to steroids rapidly and successfully. Complete and partial responses were observed in one patient each in the single-agent and combination groups; all immunotherapy-naive. In the single-agent and combination groups, seven and 14 patients experienced stable disease; seven and six patients were immunotherapy-pretreated, respectively.

CONCLUSIONS

Taminadenant, with and without spartalizumab, was well tolerated in patients with advanced NSCLC. The maximum tolerated dose of taminadenant alone was 480 mg twice-daily, and 240 mg twice-daily plus spartalizumab. Efficacy was neither a primary or secondary endpoint; however, some clinical benefit was noted regardless of prior immunotherapy or programmed cell death ligand-1 status.

Abstract 1276: Identification of S65487/VOB560 as a potent and selective intravenous 2nd-generation BCL-2 inhibitor active in wild-type and clinical mutants resistant to Venetoclax

The B-cell Lymphoma 2 (BCL-2) gene family encodes pro-apoptotic and anti-apoptotic proteins that are key regulators of the apoptotic process. Overexpression of the pro-survival member BCL-2 is a well-established mechanism contributing to oncogenesis and chemoresistance in several cancers, including lymphoma and leukemia. Venetoclax (Venclexta™), a selective BCL-2 inhibitor, is the first member of a new class of anti-cancer drugs, called BH3 mimetics, to be approved for CLL and AML. Here, we describe the identification of a novel potent and selective BCL-2 inhibitor named S65487/VOB560 that has a different binding mode on BCL-2 compared to Venetoclax. This inhibitor binds to the BH3 hydrophobic groove of BCL-2. Its selectivity profile demonstrates lack of significant binding to MCL-1, BFL-1 and poor affinity for BCL-XL. S65487/VOB560 induces apoptosis in a panel of hematological cancer cell lines and inhibits cell proliferation with IC50s in the low nM range. S65487/VOB560 induces complete regression in BCL-2-dependent RS4;11 tumors in vivo after a single IV (intravenous) administration. Strong and persistent tumor regression in xenograft models of lymphoid malignancies in mouse and rat were observed at well tolerated doses following weekly IV administration of S65487 in combination with the MCL-1-specific inhibitor, S64315/MIK665. These positive findings were further confirmed in a panel of AML PDX tumor models. Recently, acquired BCL-2 mutations (such as G101V and D103Y) were identified in patients with Chronic Lymphocytic Leukemia becoming resistant to Venetoclax. Interestingly, S65487/VOB560 is active on such BCL-2 mutants and induces apoptosis in preclinical resistance models. Altogether, these data demonstrate that S65487/VOB560 has significant therapeutic potential against human lymphoid and myeloid malignancies as well as in patients with Venetoclax resistant leukemias. Clinical studies are currently ongoing with S65487/VOB560 (NCT03755154).

Citation Format: Arnaud Le Tiran, Audrey Claperon, James Davidson, Jérôme-Benoit Starck, Thierry Le Diguarher, Maïa Chanrion, Prakash Mistry, Youzhen Wang, Elodie Monceau, Fabienne Bernhardt, Francesca Rocchetti, Gaelle Lysiak-Auvity, Ijen Chen, Zoe Daniels, Chris Pedder, Mandy Fallowfield, Jean-Michel Henlin, Imre Fejes, Janos Tatai, Miklos Nyerges, Didier Durand, Marion Zarka, Sneha Sanghavi, Anne-Marie Girard, Marie Schoumacher, Laurence Kraus-Berthier, Rick Newcombe, Ensar Halilovic, Sébastien Banquet, Alain Rupin, Heiko Maacke, James Murray, Erick Morris, Francesco Hofmann, Frédéric Colland, Olivier Geneste. Identification of S65487/VOB560 as a potent and selective intravenous 2nd-generation BCL-2 inhibitor active in wild-type and clinical mutants resistant to Venetoclax [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1276.

Reduced Mitochondrial Apoptotic Priming Drives Resistance to BH3 Mimetics in Acute Myeloid Leukemia

Acquired resistance to BH3 mimetic antagonists of BCL-2 and MCL-1 is an important clinical problem. Using acute myelogenous leukemia (AML) patient-derived xenograft (PDX) models of acquired resistance to BCL-2 (venetoclax) and MCL-1 (S63845) antagonists, we identify common principles of resistance and persistent vulnerabilities to overcome resistance. BH3 mimetic resistance is characterized by decreased mitochondrial apoptotic priming as measured by BH3 profiling, both in PDX models and human clinical samples, due to alterations in BCL-2 family proteins that vary among cases, but not to acquired mutations in leukemia genes. BCL-2 inhibition drives sequestered pro-apoptotic proteins to MCL-1 and vice versa, explaining why in vivo combinations of BCL-2 and MCL-1 antagonists are more effective when concurrent rather than sequential. Finally, drug-induced mitochondrial priming measured by dynamic BH3 profiling (DBP) identifies drugs that are persistently active in BH3 mimetic-resistant myeloblasts, including FLT-3 inhibitors and SMAC mimetics.

Maternity services in the UK during the coronavirus disease 2019 pandemic: a national survey of modifications to standard care

OBJECTIVE

To explore the modifications to maternity services across the UK, in response to the coronavirus disease 2019 (COVID-19) pandemic, in the context of the pandemic guidance issued by the Royal College of Obstetricians and Gynaecologists (RCOG), Royal College of Midwives (RCM) and NHS England.

DESIGN

National survey.

SETTING

UK maternity services during the COVID-19 pandemic.

POPULATION OR SAMPLE

Healthcare professionals working within maternity services.

METHODS

A national electronic survey was developed to investigate local modifications to general and specialist maternity care during the COVID-19 pandemic, in the context of the contemporaneous national pandemic guidance. After a pilot phase, the survey was distributed through professional networks by the RCOG and co-authors. The survey results were presented descriptively in tabular and graphic formats, with proportions compared using chi-square tests.

MAIN OUTCOME MEASURES

Service modifications made during the pandemic.

RESULTS

A total of 81 respondent sites, 42% of the 194 obstetric units in the UK, were included. They reported substantial and heterogeneous maternity service modifications. Seventy percent of units reported a reduction in antenatal appointments and 56% reported a reduction in postnatal appointments; 89% reported using remote consultation methods. A change to screening pathways for gestational diabetes mellitus was reported by 70%, and 59% had temporarily removed the offer of births at home or in a midwife-led unit. A reduction in emergency antenatal presentations was experienced by 86% of units.

CONCLUSIONS

This national survey documents the extensive impact of the COVID-19 pandemic on maternity services in the UK. More research is needed to understand the impact on maternity outcomes and experience.

TWEETABLE ABSTRACT

A national survey showed that UK maternity services were modified extensively and heterogeneously in response to COVID-19.

Coronavirus in pregnancy and delivery: rapid review

OBJECTIVES

There are limited case series reporting the impact on women affected by coronavirus during pregnancy. In women affected by severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), the case fatality rate appears higher in those affected in pregnancy compared with non-pregnant women. We conducted a rapid review to guide health policy and management of women affected by COVID-19 during pregnancy, which was used to develop the Royal College of Obstetricians and Gynaecologists' (RCOG) guidelines on COVID-19 infection in pregnancy.

METHODS

Searches were conducted in PubMed and MedRxiv to identify primary case reports, case series, observational studies and randomized controlled trials describing women affected by coronavirus in pregnancy. Data were extracted from relevant papers. This review has been used to develop guidelines with representatives of the Royal College of Paediatrics and Child Health (RCPCH) and RCOG who provided expert consensus on areas in which data were lacking.

RESULTS

From 9965 search results in PubMed and 600 in MedRxiv, 21 relevant studies, all of which were case reports or case series, were identified. From reports of 32 women to date affected by COVID-19 in pregnancy, delivering 30 babies (one set of twins, three ongoing pregnancies), seven (22%) were asymptomatic and two (6%) were admitted to the intensive care unit (ICU), one of whom remained on extracorporeal membrane oxygenation. No maternal deaths have been reported to date. Delivery was by Cesarean section in 27 cases and by vaginal delivery in two, and 15 (47%) delivered preterm. There was one stillbirth and one neonatal death. In 25 babies, no cases of vertical transmission were reported; 15 were reported as being tested with reverse transcription polymerase chain reaction after delivery. Case fatality rates for SARS and MERS were 15% and 27%, respectively. SARS was associated with miscarriage or intrauterine death in five cases, and fetal growth restriction was noted in two ongoing pregnancies affected by SARS in the third trimester.

CONCLUSIONS

Serious morbidity occurred in 2/32 women with COVID-19, both of whom required ICU care. Compared with SARS and MERS, COVID-19 appears less lethal, acknowledging the limited number of cases reported to date and that one woman remains in a critical condition. Preterm delivery affected 47% of women hospitalized with COVID-19, which may put considerable pressure on neonatal services if the UK's reasonable worst-case scenario of 80% of the population being affected is realized. Based on this review, RCOG, in consultation with RCPCH, developed guidance for delivery and neonatal care in pregnancies affected by COVID-19, which recommends that delivery mode be determined primarily by obstetric indication and recommends against routine separation of affected mothers and their babies. We hope that this review will be helpful for maternity and neonatal services planning their response to COVID-19. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Coronavirus in pregnancy and delivery: rapid review

OBJECTIVES

There are limited case series reporting the impact on women affected by coronavirus during pregnancy. In women affected by severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), the case fatality rate appears higher in those affected in pregnancy compared with non-pregnant women. We conducted a rapid review to guide health policy and management of women affected by COVID-19 during pregnancy, which was used to develop the Royal College of Obstetricians and Gynaecologists' (RCOG) guidelines on COVID-19 infection in pregnancy.

METHODS

Searches were conducted in PubMed and MedRxiv to identify primary case reports, case series, observational studies and randomized controlled trials describing women affected by coronavirus in pregnancy. Data were extracted from relevant papers. This review has been used to develop guidelines with representatives of the Royal College of Paediatrics and Child Health (RCPCH) and RCOG who provided expert consensus on areas in which data were lacking.

RESULTS

From 9965 search results in PubMed and 600 in MedRxiv, 21 relevant studies, all of which were case reports or case series, were identified. From reports of 32 women to date affected by COVID-19 in pregnancy, delivering 30 babies (one set of twins, three ongoing pregnancies), seven (22%) were asymptomatic and two (6%) were admitted to the intensive care unit (ICU), one of whom remained on extracorporeal membrane oxygenation. No maternal deaths have been reported to date. Delivery was by Cesarean section in 27 cases and by vaginal delivery in two, and 15 (47%) delivered preterm. There was one stillbirth and one neonatal death. In 25 babies, no cases of vertical transmission were reported; 15 were reported as being tested with reverse transcription polymerase chain reaction after delivery. Case fatality rates for SARS and MERS were 15% and 27%, respectively. SARS was associated with miscarriage or intrauterine death in five cases, and fetal growth restriction was noted in two ongoing pregnancies affected by SARS in the third trimester.

CONCLUSIONS

Serious morbidity occurred in 2/32 women with COVID-19, both of whom required ICU care. Compared with SARS and MERS, COVID-19 appears less lethal, acknowledging the limited number of cases reported to date and that one woman remains in a critical condition. Preterm delivery affected 47% of women hospitalized with COVID-19, which may put considerable pressure on neonatal services if the UK's reasonable worst-case scenario of 80% of the population being affected is realized. Based on this review, RCOG, in consultation with RCPCH, developed guidance for delivery and neonatal care in pregnancies affected by COVID-19, which recommends that delivery mode be determined primarily by obstetric indication and recommends against routine separation of affected mothers and their babies. We hope that this review will be helpful for maternity and neonatal services planning their response to COVID-19. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Menopause, cognition and dementia - A review

There is increasing evidence that menopausal changes can have an impact on women’s cognition and potentially, the future development of dementia. In particular, the role of reduced levels of estrogen in postmenopausal changes has been linked to an increased risk of developing dementia in observational studies. Not surprisingly, this has led to several clinical trials investigating whether postmenopausal hormone replacement therapy can potentially delay/avoid cognitive changes and subsequently, the onset of dementia. However, the evidence of these trials has been mixed, with some showing positive effects while others show no or even negative effects. In the current review, we investigate this controversy further by reviewing the existing studies and trials in cognition and dementia. Based on the current evidence, we conclude that previous approaches may have used a mixture of women with different genetic risk factors for dementia which might explain these contradicting findings. Therefore, it is recommended that future interventional studies take a more personalised approach towards hormone replacement therapy use in postmenopausal women, by taking into account the women’s genetic status for dementia risk.

Perceived Racial/Ethnic Discrimination Predicts Worse Global Cognition in a Diverse Sample

Objective

While perceived racial/ethnic discrimination (PD) and HIV can be independently detrimental to cognitive function, it is unclear whether persons living with HIV (PLWH) who experience PD may be at risk for greater cognitive dysfunction than HIV- persons. In a diverse sample, we hypothesized that PD would be related to worse cognition and that this effect would be moderated by HIV status.

Participants and Method

This cross-sectional study included 53 participants (57% PLWH; 77% African American and 23% Latinx; 45% male; M Age = 54.5 ± 6.1 years; M Education = 12.4 ± 2.2 years) who completed the Perceived Ethnic Discrimination Questionnaire (PEDQ) and a neurocognitive (NC) battery. Variables included education (years); HIV status; PEDQ Total Score and global NC T-score (averaged, demographically-corrected T-scores for all tests). A general linear model examined main and interaction effects of HIV status and PD on global cognitive function. Covariates included depression and urine toxicology status for cocaine and marijuana.

Results

Greater PD was associated with higher education and greater depression. The model showed that greater PD (β = -.48, p &lt; .05) and lower education (β = -19.0, p &lt; .01) were related to worse global cognitive function. This relationship was moderated by education (β = .59, p &lt; .01), such that the relationship between PD and global cognitive function was stronger in those with higher education. There was no main effect of HIV or HIV*PD interaction on global cognitive function.

Conclusions

This study demonstrated that greater PD is related to worse global cognitive function and this relationship is stronger in those with more education. While no causal factors can be attributed, racial/ethnic minorities with higher education may be granted greater access to areas with greater structural racism and/or microagressions (i.e., predominantly white workplaces). Future studies should evaluate the role of socioeconomic and workplace diversity when considering discrimination.

Abstract 342: S63845, a novel BH3 mimetic Mcl-1 inhibitor synergizes with midostaurin to induce potent apoptosis in acute myeloid leukemia cells carrying FLT3-ITD mutations

Myeloid cell leukemia 1 (Mcl-1) is one of the key anti-apoptotic Bcl-2 family proteins that binds and neutralizes pro-apoptotic BIM, BAX and BAK at the mitochondrial outer membrane, preventing cytochrome c release and caspase activation. Selective upregulation of Mcl-1 functionally contributes to resistance of acute myeloid leukemias (AML) with FMS-like tyrosine kinase-3-internal tandem duplications (FLT3-ITD) to chemotherapy (Kasper S. et al. 2012, Blood Cancer J. 2:e60, doi:10.1038/bcj.2012.5). Here we show that a novel Mcl-1 inhibitor S63845 (Kotschy A. et al. 2016, Nature 538, 477-482), has synergistic proapoptotic activity in combination with FLT3-ITD kinase inhibitor midostaurin in pre-clinical models of AML. Our studies demonstrate that S63845 has potent single agent activity in AML cell lines and primary AML samples harboring FLT3-ITD with IC50 values in low nanomolar range. Co-targeting of Mcl-1 and FLT3-ITD with S63845 and midostaurin, respectively, significantly increased apoptosis in FLT3-ITD cells with caspase-3 activation and PARP cleavage occurring rapidly within 6 hours of treatment. Consistent with markedly reduced cell growth and viability, analysis of drug combinations efficacy using Bliss independence model revealed strong synergistic interactions between S63845 and midostaurin in FLT3-ITD cell lines and primary AML samples. Midostaurin caused de-phosphorylation of FLT3-ITD and its downstream targets such as STAT5, AKT and MAPK. This was accompanied by significant downregulation of MAPK-mediated phosphorylation of Mcl-1 at Thr163 required for Mcl-1 stability. Consequently, midostaurin reduced Mcl-1 protein levels, with no major changes in antiapoptotic Bcl-2 or Bcl-XL. Importantly, midostaurin increased expression of pro-apoptotic Bim, which could in turn bind and negate residual Mcl-1 pro-survival activity. Elevated Bim was sustained upon S63845 co-treatment, suggesting that Bim plays functional role in midostaurin/S63845-mediated lethality. Dynamic BH3 profiling showed that midostaurin primed FLT3-ITD cells to Mcl-1 and Bcl-2 inhibitors and facilitated general apoptosis priming in response to Bim peptide. Importantly, given that Mcl-1 is a major contributing factor to resistance of AML to Bcl-2 selective BH3-mimetic venetoclax, S63845/midostaurin treatment induced cell death in venetoclax-resistant FLT3-ITD mutants. In summary, S63845/midostaurin is highly synergistic in FLT3-ITD mutated AML cells including those resistant to venetoclax. In vivo experiments of tolerability and efficacy are ongoing and will be reported.

Citation Format: Anna Skwarska, Qi Zhang, Shelley M. Herbrich, Natalia Baran, Ensar Halilovic, Peter Ruvolo, Vivian Ruvolo, Erick Morris, Andrew Wei, Donia Moujalled, Michael Andreff, Marina Konopleva. S63845, a novel BH3 mimetic Mcl-1 inhibitor synergizes with midostaurin to induce potent apoptosis in acute myeloid leukemia cells carrying FLT3-ITD mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 342.

Abstract 4482: S64315 (MIK665) is a potent and selective Mcl1 inhibitor with strong antitumor activity across a diverse range of hematologic tumor models

Mcl-1 is highly expressed in a variety of human cancers (including those of hematopoietic and lymphoid origin) and is exploited by cancer cells to evade cell death and to develop resistance to diverse chemotherapeutic agents. We disclose, for the first time, the structure of S64315 (also named MIK665) a highly potent and selective inhibitor of Mcl-1 with improved potency over its predecessor S63845 (Kotschy et al, Nature, 2016). S64315/MIK665 is currently in phase 1 in AML (Acute Myeloid Leukemia) and MDS (Myelodysplastic Syndrome) (EudraCT 2016-003768-38, NCT 02979366) and in MM (Multiple Myeloma) and lymphoma (NCT02992483). A fragment-based, structure-guided drug discovery effort led to the identification of S64315/MIK665 that binds to human Mcl-1 with a sub-nanomolar affinity (Ki 0.048 nM) and selectively over other anti-apoptotic Bcl-2 family members. It has similar affinity for human, rat, dog and monkey Mcl-1 but about a ten-fold lower affinity for mouse Mcl-1. S64315/MIK665 causes dose-dependent activation of the intrinsic apoptosis pathway in a Bax/Bak-dependent manner, as measured by increased caspase activity and cleaved PARP. S64315/MIK665 shows strong cell killing activity in a diverse panel of human hematological tumor cell lines, including AML, lymphoma and MM. The activity profile of S64315/MIK665 is distinct from that of venetoclax, a selective Bcl2 inhibitor. In vivo, S64315 as single agent demonstrated potent and dose-dependent apoptotic and antitumor response after intravenous administration in several human hematological tumor models grafted in immuno-compromised mice and rats. Complete regression of established tumors, at well tolerated doses, was achieved using different intravenous dosing regimens in rats as well as in mice. Finally, dual BH3-mimetic targeting approach combining S64315/MIK665 with BCL2 inhibitors showed strong and durable antitumor responses in several hematological tumor models both in vitro and in vivo.

Citation Format: Ana Leticia Maragno, Prakash Mistry, András Kotschy, Zoltán Szlavik, James Murray, James Davidson, Gaëtane Le Toumelin-Braizat, Maïa Chanrion, Alain Bruno, Audrey Claperon, Heiko Maacke, Erick Morris, Youzhen Wang, Alix Derreal, Márton Csekei, Attila Paczal, Zoltán Szabo, Szabolcs Sipos, Agnes Proszenyak, Balázs Balint, Allan Surgenor, Pawel Dokurno, Natalia Matassova, Ijen Chen, Gaëlle Lysiak-Auvity, Anne-Marie Girard, Fabienne Grave, Frédéric Colland, Ensar Halilovic, Olivier Geneste. S64315 (MIK665) is a potent and selective Mcl1 inhibitor with strong antitumor activity across a diverse range of hematologic tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4482.

Abstract 257: Targeting AML through apoptosis activation using Bcl-2/Mcl-1 or Bcl-2/Hdm2 inhibitor combination therapies

Acute myeloid leukemia (AML) is an aggressive and heterogeneous hematologic malignancy, characterized by uncontrolled proliferation and impaired differentiation of myeloid cells. With the exception of certain subtypes, the average long-term survival rate remains low, thus underlining the need to further improve the outcome of AML patients. Since AML is one of the least mutated cancer types, the majority of AML patients may not carry targetable genetic alterations. However, the anti-apoptotic proteins of the Bcl-2 family, such as Bcl-2 and Mcl-1, are often overexpressed in AML, allowing deregulated survival; hence pro-apoptosis priming with small molecule inhibitors of Bcl-2 and Mcl-1 may provide a broader therapeutic benefit across the disease. In addition, a majority of AML patients carry wild-type p53, providing therapeutic opportunity for Hdm2 inhibitors to stabilize p53 and lead to expression of pro-apoptotic molecules (e.g., PUMA & BAX). Therefore, targeting the combined apoptosis mechanisms by inhibiting different anti-apoptotic Bcl-2 family of proteins and activating p53 concomitantly may synergistically enhance apoptotic cell death of AML tumor cells.

We tested the combination of Bcl-2 inhibitors (BCL201/S55746 or venetoclax) with either MIK665/S64315, a novel and selective inhibitor of Mcl-1 or HDM201, a selective small molecule inhibitor of p53:Hdm2 interaction, in a series of in vitro and in vivo studies in AML. In vitro, strong combination synergy was observed with a remarkable induction of cell death for both combinations. In vivo, the combination of Bcl-2 inhibitors with MIK665/S64315 or HDM201 lead to complete and durable antitumor responses in a variety of p53wt AML patient-derived xenograft models of heterogeneous genetic profiles. Notably, lowering the dose of HDM201 by 4 fold from its most efficacious dose, resulted in a high degree of tumor regressions while mitigating the toxicity effects on platelets. Taken together, these data demonstrate that a combination of Bcl-2 inhibitor (BCL201/S55746 or venetoclax) with MIK665/S64315 or HDM201 provide therapeutic benefit over the monotherapy, and support a rationale for testing these apoptosis enhancing combination approaches in AML patients.

Citation Format: Youzhen Wang, Shumei Qui, Sneha Sanghavi, Iain Mulford, Gaëlle Lysiak, Maïa Chanrion, Prakash Mistry, Ulrike Pfaar, Marie Schoumacher, Audrey Claperon, Laurence Kraus-Berthier, Sébastien Banquet, Alix Derreal, Claire Fabre, Heiko Maacke, Frédéric Colland, Olivier Geneste, Erick Morris, Ensar Halilovic. Targeting AML through apoptosis activation using Bcl-2/Mcl-1 or Bcl-2/Hdm2 inhibitor combination therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 257.

Abstract 4477: MIK665/S64315, a novel Mcl-1 inhibitor, in combination with Bcl-2 inhibitors exhibits strong synergistic antitumor activity in a range of hematologic malignancies

One of the hallmarks of cancer is evasion of apoptosis. The B-cell lymphoma-2 (Bcl-2) family of proteins represents a crucial point of control of apoptosis. The Bcl-2 family comprises both pro- and anti-apoptotic members, the latter of which (Bcl-2, Bcl-xL, Bcl-w, Mcl-1 and Bcl-2A1) are often overexpressed in cancer cells, supporting their aberrant survival. Thus, these anti-apoptotic proteins have become an attractive target for cancer therapy. BH3 mimetics have been shown to bind to the BH3 binding groove of anti-apoptotic Bcl-2 family members and inhibit their function, resulting in apoptotic cell death, and one such BH3 mimetic, ABT-199 (venetoclax), has recently been approved for treatment of relapsed or refractory Chronic Lymphocytic Leukemia. We have developed two novel and potent BH3 mimetics: MIK665/S64315, a highly selective inhibitor of Mcl-1 and BCL201/S55746, a selective Bcl-2 inhibitor. Both compounds, individually induce apoptosis in hematological cancer cell lines, primary patient samples and demonstrate anti-tumor efficacy in xenograft models. MIK665/S64315 is currently in phase 1 clinical development in AML and MDS (NCT 02979366) and in MM and lymphoma (NCT02992483). Here, we describe the activity of the combination of MIK665/S64315 with BCL201/S55746 or venetoclax, both in vitro and in vivo, across a range of hematological indications (AML, MM and DLBCL). In vitro, a strong synergy was observed with these combinations, resulting in a remarkable induction of cell death in majority of cell lines tested. In vivo, MIK665/S64315 and BCL201/S55746 combinations lead to complete and durable antitumor responses in many different xenograft models in mice and rats. Taken together, these data demonstrate that a combination of MIK665/S64315 and BCL201/S55746 provide strong therapeutic benefit over either monotherapy, and support a rationale for testing Mcl-1 and Bcl-2 inhibitor combinations in patients with hematological malignancies.

Citation Format: Ensar Halilovic, Maïa Chanrion, Prakash Mistry, Markus Wartmann, Shumei Qiu, Sneha Sanghavi, Yan Chen, Gaëlle Lysiak, Ana Leticia Maragno, Ulrike Pfaar, Felix Huth, Marie Schoumacher, Audrey Claperon, Laurence Kraus-Berthier, Sébastien Banquet, Alix Derreal, Heiko Maacke, Frédéric Colland, Olivier Geneste, Erick Morris, Youzhen Wang. MIK665/S64315, a novel Mcl-1 inhibitor, in combination with Bcl-2 inhibitors exhibits strong synergistic antitumor activity in a range of hematologic malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4477.

Abstract 381: Combined inhibition of Bcl-2 and MCL-1 in small cell lung cancer (SCLC) is most effective in tumors with low Bcl-xL expression

Introduction: SCLC is an aggressive high-grade neuroendocrine malignancy in which targeting anti-apoptotic regulators such as Bcl-2 and Bcl-xL has shown efficacy in pre-clinical models but has not resulted in successful clinical trials (Rudin et al., Clin Cancer Res. 2012). Although SCLC cell-lines do not reflect the clinical impact of these inhibitors, patient-derived xenograft (PDX) models may more accurately recapitulate Bcl-2 family expression profiles and BH3 mimetic efficacy. One promising hypothesis is that the fellow anti-apoptotic protein MCL-1 rescues viability in the presence of Bcl-2/Bcl-xL antagonists. Here we evaluate the efficacy of the MCL-1 inhibitor S63845 in combination with a novel specific inhibitor of Bcl-2, BCL201/S55746, in SCLC patient-derived xenografts. Methods: BH3 mimetic compounds were tested for synergy in vitro in SCLC cell lines. A set of ten cell lines was chosen based on relative expression of BCL2, MCL1, and BCL2L1 (Bcl-xL) mRNA. Single agent and and pair-wise combinations of Bcl2 family inhibitors were compared in three-day growth inhibition assays. Loewe synergy scores were plotted versus Bcl2 family mRNA expression to identify the determinants of drug sensitivity. Based on the cell line synergy assays, a combination of BCL201/S55746 and S63845 was selected to test in PDX models of SCLC. Bcl-2 family expression was profiled across a panel of 37 SCLC PDX models generated at MGH by quantitative western blot, and standardized to the most sensitive SCLC cell line, NCI-H211. Ten models were selected based on absolute expression of Bcl-2, Bcl-xL and MCL-1. Mice were treated when subcutaneous tumors reached a volume of 400-800 cc, enabling precise measurement of tumor regression and time to tumor regrowth. Findings: Bcl-2 family dependency in SCLC cell lines was profiled with selective inhibitors as single agents or combinations. Maximum synergy was found between BCL201/S55746 and S63845 in cell lines with the highest Bcl-2:Bcl-xL expression ratio. Bcl-2 family expression was profiled across a panel of 37 PDX models of SCLC, and a representative set of 10 models was selected for in vivo testing. Consistent with cell line results, the two most sensitive models to BCL201/S55746+S63845 demonstrated the highest Bcl-2:Bcl-xL ratios, with moderate to high expression of MCL-1. In these models BCL201/S55746+S63845 resulted in a 44-70% tumor regression that was stable throughout 4 weeks of treatment. Efficacy was not dependent on MCL-1 expression, and was not strongly correlated with PDX sensitivity to platinum-etoposide. Conclusions: Combined inhibition of Bcl-2 with BCL201 and MCL-1 with S63845 is effective in SCLC tumors with relatively low Bcl-xL expression. This combination overcomes MCL-1 mediated resistance to Bcl-2 inhibitors, and represents a promising strategy to target anti-apoptotic dependency in SCLC.

Citation Format: Benjamin J. Drapkin, Sneha Sanghavi, David T. Myers, Jun Zhong, Sarah Phat, Youzhen Wang, Ensar Halilovic, Javad Golji, Anna Farago, Erick Morris, Nicholas J. Dyson. Combined inhibition of Bcl-2 and MCL-1 in small cell lung cancer (SCLC) is most effective in tumors with low Bcl-xL expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 381.

Combining BH3-mimetics to target both BCL-2 and MCL1 has potent activity in pre-clinical models of acute myeloid leukemia

Improving outcomes in acute myeloid leukemia (AML) remains a major clinical challenge. Overexpression of pro-survival BCL-2 family members rendering transformed cells resistant to cytotoxic drugs is a common theme in cancer. Targeting BCL-2 with the BH3-mimetic venetoclax is active in AML when combined with low-dose chemotherapy or hypomethylating agents. We now report the pre-clinical anti-leukemic efficacy of a novel BCL-2 inhibitor S55746, which demonstrates synergistic pro-apoptotic activity in combination with the MCL1 inhibitor S63845. Activity of the combination was caspase and BAX/BAK dependent, superior to combination with standard cytotoxic AML drugs and active against a broad spectrum of poor risk genotypes, including primary samples from patients with chemoresistant AML. Co-targeting BCL-2 and MCL1 was more effective against leukemic, compared to normal hematopoietic progenitors, suggesting a therapeutic window of activity. Finally, S55746 combined with S63845 prolonged survival in xenograft models of AML and suppressed patient-derived leukemia but not normal hematopoietic cells in bone marrow of engrafted mice. In conclusion, a dual BH3-mimetic approach is feasible, highly synergistic, and active in diverse models of human AML. This approach has strong clinical potential to rapidly suppress leukemia, with reduced toxicity to normal hematopoietic precursors compared to chemotherapy.

Clinicopathological, genomic and immunological factors in colorectal cancer prognosis

BACKGROUND

Numerous factors affect the prognosis of colorectal cancer (CRC), many of which have long been identified, such as patient demographics and the multidisciplinary team. In more recent years, molecular and immunological biomarkers have been shown to have a significant influence on patient outcomes. Whilst some of these biomarkers still require ongoing validation, if proven to be worthwhile they may change our understanding and future management of CRC. The aim of this review was to identify the key prognosticators of CRC, including new molecular and immunological biomarkers, and outline how these might fit into the whole wider context for patients.

METHODS

Relevant references were identified through keyword searches of PubMed and Embase Ovid SP databases.

RESULTS

In recent years there have been numerous studies outlining molecular markers of prognosis in CRC. In particular, the Immunoscore® has been shown to hold strong prognostic value. Other molecular biomarkers are useful in guiding treatment decisions, such as mutation testing of genes in the epidermal growth factor receptor pathway. However, epidemiological studies continue to show that patient demographics are fundamental in predicting outcomes.

CONCLUSION

Current strategies for managing CRC are strongly dependent on clinicopathological staging, although molecular testing is increasingly being implemented into routine clinical practice. As immunological biomarkers are further validated, their testing may also become routine. To obtain clinically useful information from new biomarkers, it is important to implement them into a model that includes all underlying fundamental factors, as this will enable the best possible outcomes and deliver true precision medicine.

A step-wise approach to developing indicators to compare the performance of maternity units using hospital administrative data

Hospital administrative data are attractive for comparing performance of maternity units because of their often large sample sizes, lack of selection bias and the relatively low costs of accessing these data compared with conducting primary data collection. However, using administrative data to develop indicators can also present challenges including varying data quality, the limited detail on clinical risk factors and a lack of structural and user experience measures. This review illustrates how to develop performance indicators for maternity units using hospital administrative data, including methods to address the challenges that administrative data pose.

TWEETABLE ABSTRACT

How to develop maternity indicators from administrative data.

Baseline biomarkers of connectome disruption and atrophy predict future processing speed in early multiple sclerosis

The development of accurate prognoses in multiple sclerosis is difficult, as the disease is characterized by heterogeneous patterns of brain abnormalities that relate in an unclear way to future impairments. Here, we use a statistical modeling approach to determine if the baseline pattern of connectome disruption due to T2-FLAIR lesions could predict a patient's future processing speed, as measured using the Symbol Digits Modality Test scores. Imaging data, demographics and Symbol Digits Modality Test scores were collected from 61 early relapsing remitting multiple sclerosis patients. The Network Modification Tool was used to estimate damage to the connectome by quantifying white matter abnormalities' effects on 1) global network properties, 2) regional connectivity and 3) connectivity between pairs of regions. MS subjects showed significant improvement of processing speed between baseline and follow-up (t = −2.6, p = 0.0096); however, both baseline (t = −4.01, p = 0.00012) and follow-up (t = −2.10, p = 0.038) processing speed were significantly lower than age-matched healthy controls. Partial Least Squares Regression was used to create models that predict future processing speed from between baseline imaging metrics and demographics. The model based on region-pair disconnection and gray matter atrophy had the lowest AIC and highest prediction accuracy (R² = 0.79) compared to models based on global (R² = 0.41) or regional (R² = 0.66) disconnection and gray matter atrophy, overlap with an ROI-based atlas and gray matter atrophy (R² = 0.73) or gray matter atrophy alone (R² = 0.71). We found that baseline measures of connectivity disruption in various parietal, temporal, occipital and subcortical regions and atrophy in the putamen were important predictors of future processing speed. We conclude that information about disruptions to pairwise brain connections is more informative of future processing speed than regional or global metrics or gray matter atrophy alone. The combination of quantitative disconnectome metrics, gray matter atrophy and statistical modeling approaches could enable clinicians in developing more accurate, individualized prognoses of future cognitive status in multiple sclerosis patients.

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Atrophy and structural disconnection estimates via NeMo Tool were collected in MS.

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Future cognitive functioning in MS patients was predicted by baseline MRI measures.

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Measures of atrophy and disconnection between region-pairs had best goodness-of-fit.

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More caudate atrophy was significantly predictive of worse future cognition.

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Disconnections in parietal/temporal/occipital areas predicted worse future cognition.

S55746 is a novel orally active BCL-2 selective and potent inhibitor that impairs hematological tumor growth

Escape from apoptosis is one of the major hallmarks of cancer cells. The B-cell Lymphoma 2 (BCL-2) gene family encodes pro-apoptotic and anti-apoptotic proteins that are key regulators of the apoptotic process. Overexpression of the pro-survival member BCL-2 is a well-established mechanism contributing to oncogenesis and chemoresistance in several cancers, including lymphoma and leukemia. Thus, BCL-2 has become an attractive target for therapeutic strategy in cancer, as demonstrated by the recent approval of ABT-199 (Venclexta™) in relapsed or refractory Chronic Lymphocytic Leukemia with 17p deletion. Here, we describe a novel orally bioavailable BCL-2 selective and potent inhibitor called S55746 (also known as BCL201). S55746 occupies the hydrophobic groove of BCL-2. Its selectivity profile demonstrates no significant binding to MCL-1, BFL-1 (BCL2A1/A1) and poor affinity for BCL-XL. Accordingly, S55746 has no cytotoxic activity on BCL-XL-dependent cells, such as platelets. In a panel of hematological cell lines, S55746 induces hallmarks of apoptosis including externalization of phosphatidylserine, caspase-3 activation and PARP cleavage. Ex vivo, S55746 induces apoptosis in the low nanomolar range in primary Chronic Lymphocytic Leukemia and Mantle Cell Lymphoma patient samples. Finally, S55746 administered by oral route daily in mice demonstrated robust anti-tumor efficacy in two hematological xenograft models with no weight lost and no change in behavior. Taken together, these data demonstrate that S55746 is a novel, well-tolerated BH3-mimetic targeting selectively and potently the BCL-2 protein.

Quantitative Susceptibility Mapping of the Thalamus: Relationships with Thalamic Volume, Total Gray Matter Volume, and T2 Lesion Burden

BACKGROUND AND PURPOSE

Both thalamic iron deposition and atrophy have been reported in patients with multiple sclerosis compared with healthy controls, but how they are related is unclear. The purpose of this study was to understand the pathophysiologic basis for this iron deposition.

MATERIALS AND METHODS

Ninety-five patients with relapsing-remitting multiple sclerosis underwent 3T MR imaging with a standardized protocol that included quantitative susceptibility mapping to measure iron concentration and a 3D T1 echo-spoiled gradient-echo sequence to obtain thalamic volumes. Volumes of interest were manually delineated on the quantitative susceptibility map to encompass both thalami. Multivariate regression analyses were performed to identify the association between thalamic susceptibility and volume. Associations between thalamic susceptibility and total gray matter volume, cortical thickness, and T2 lesion volume were also assessed.

RESULTS

The relative susceptibility of the thalamus was associated with T2 lesion volume (P = .015) and was higher in the presence of enhancing lesions (P = .013). The relative susceptibility of the thalami was not associated with thalamic volumes, total gray matter volumes, or cortical thickness (P > .05).

CONCLUSIONS

Iron levels in the thalami are associated with T2 lesion burden and the presence of enhancing lesions, but not with thalamic or gray matter volumes, suggesting that iron accumulation is associated with white matter inflammation rather than gray matter neurodegeneration.