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Communications Chemistry Feb 2024Pomalidomide is an E3 ligase recruiter exploited by PROTACs to degrade target proteins, but its application is hampered by the off-target degradation of other vital...
Pomalidomide is an E3 ligase recruiter exploited by PROTACs to degrade target proteins, but its application is hampered by the off-target degradation of other vital endogenous zinc finger (ZF) proteins. Now, the off-target ZF binding of pomalidomide-based PROTACs is evaluated by a high-throughput imaging screening platform, and minimization of off-target degradation as well as enhanced potency are achieved through selective functionalization at the C5 position of the phthalimide ring.
PubMed: 38409444
DOI: 10.1038/s42004-024-01125-2 -
Blood Advances Oct 2023We conducted a phase 1/2 study of carfilzomib, pomalidomide, and dexamethasone (KPd) and KPd with daratumumab (Dara-KPd) in relapsed/refractory multiple myeloma. The...
We conducted a phase 1/2 study of carfilzomib, pomalidomide, and dexamethasone (KPd) and KPd with daratumumab (Dara-KPd) in relapsed/refractory multiple myeloma. The primary end points were identification of a maximum tolerated dose (MTD) of KPd for phase 1, and rates of overall response (ORR) and near complete response (nCR) after 4 cycles of KPd and Dara-KPd, respectively, for phase 2. The MTD for KPd was carfilzomib 20/27 mg/m2 on days 1, 2, 8, 9, 15, and 16 (cycles 1-8) and days 1, 2, 15, and 16 for cycles 9 and beyond; oral pomalidomide 4 mg on days 1 to 21; and oral dexamethasone 40 mg weekly in 28-day cycles. Sixty-six patients received KPd, including 34 at the MTD. The ORR after 4 cycles of KPd at the MTD was 27/34 (79%; 95% confidence interval [CI], 62%-91%), meeting the statistical threshold for efficacy. At a median follow-up of 44 months, the median progression-free survival (PFS) was 13 months and overall survival (OS) 44 months. Twenty-eight patients received Dara-KPd. The rate of nCR or better after 4 cycles was 11/28 (39%; 95% CI, 22%-59%), meeting the statistical threshold for efficacy. As the best response to Dara-KPd, the ORR was 25/28 (89%) and the rate of measurable residual disease negativity by flow cytometry (10-5) was 17/26 (65%). At a median follow-up of 26 months, the median PFS and OS for Dara-KPd were not reached. Dara-KPd induced deeper and more durable responses than KPd without compromising safety in a predominantly high-risk, lenalidomide-refractory population, warranting further evaluation of this quadruplet. This trial is registered at www.clinicaltrials.gov as #NCT01665794.
Topics: Humans; Multiple Myeloma; Antineoplastic Combined Chemotherapy Protocols; Dexamethasone
PubMed: 36763537
DOI: 10.1182/bloodadvances.2022008866 -
Nature Communications Nov 2023Temporal control of protein levels in cells and living animals can be used to improve our understanding of protein function. In addition, control of engineered proteins...
Temporal control of protein levels in cells and living animals can be used to improve our understanding of protein function. In addition, control of engineered proteins could be used in therapeutic applications. PRoteolysis-TArgeting Chimeras (PROTACs) have emerged as a small-molecule-driven strategy to achieve rapid, post-translational regulation of protein abundance via recruitment of an E3 ligase to the target protein of interest. Here, we develop several PROTAC molecules by covalently linking the antibiotic trimethoprim (TMP) to pomalidomide, a ligand for the E3 ligase, Cereblon. These molecules induce degradation of proteins of interest (POIs) genetically fused to a small protein domain, E. coli dihydrofolate reductase (eDHFR), the molecular target of TMP. We show that various eDHFR-tagged proteins can be robustly degraded to 95% of maximum expression with PROTAC molecule 7c. Moreover, TMP-based PROTACs minimally affect the expression of immunomodulatory imide drug (IMiD)-sensitive neosubstrates using proteomic and biochemical assays. Finally, we show multiplexed regulation with another known degron-PROTAC pair, as well as reversible protein regulation in a rodent model of metastatic cancer, demonstrating the formidable strength of this system. Altogether, TMP PROTACs are a robust approach for selective and reversible degradation of eDHFR-tagged proteins in vitro and in vivo.
Topics: Animals; Tetrahydrofolate Dehydrogenase; Proteolysis Targeting Chimera; Escherichia coli Proteins; Escherichia coli; Trimethoprim; Proteomics; Ubiquitin-Protein Ligases; Proteolysis
PubMed: 37923771
DOI: 10.1038/s41467-023-42820-3 -
EJHaem Nov 2023Pomalidomide-dexamethasone (Pd) has been a standard care treatment for relapsed and refractory multiple myeloma since 2013. However, the outcomes of Pd after exposure to...
Pomalidomide-dexamethasone (Pd) has been a standard care treatment for relapsed and refractory multiple myeloma since 2013. However, the outcomes of Pd after exposure to CD38 antibodies are not known. Here we describe the real-world use and efficacy of pomalidomide in a Danish, nationwide cohort of daratumumab-exposed patients. We identified 328 patients that were treated with pomalidomide. Of these, 137 received Pd, 65 daratumumab-pomalidomide-dexamethasone (DPd), 43 pomalidomide-cyclophosphamide-dexamethasone (PCd), 19 carfilzomib-pomalidomide-dexamethasone (KPD), 11 pomalidomide-bortezomib-dexamethasone (PVd), and 52 pomalidomide in other combinations. Patients treated with Pd in this cohort had a partial response or better (≥ PR) rate of 35.8% and median time to next treatment (mTNT) of 4.9 months, almost identical to the results of previous prospective clinical trials. Although treatment with the various pomalidomide-containing triplet regimens resulted in higher ≥ PR rates (PCd: 46.5%, PVd: 63.6%, DPd: 55.4%, KPd: 63.2%), the mTNT achieved was not significantly better than with Pd in most cases (PCD: 5.4, PVD: 5.3, DPD: 4.7 months). The exception to this was KPd (mTNT 7.4 months), but this regimen was mainly used earlier in the course of the disease (median time from diagnosis 2.3 years vs. 3.7-4.3 years). The most important predictor of outcomes was not the choice of index regimen ( = 0.72), but prior exposure ( = 0.0116). Compared to CD38 antibody-naïve patients, triple-class-exposed patients achieved reduced ≥ PR rate (38.0% vs. 47.3%), shorter mTNT (4.0 vs. 5.9 months), and shorter median overall survival (12.4 vs. 24.2 months) with pomalidomide treatment.
PubMed: 38024635
DOI: 10.1002/jha2.774 -
Haematologica Feb 2024The primary and pre-specified updated analyses of ICARIA-MM (NCT02990338) demonstrated improved progression-free survival and a benefit in overall survival (OS) was...
The primary and pre-specified updated analyses of ICARIA-MM (NCT02990338) demonstrated improved progression-free survival and a benefit in overall survival (OS) was reported with the addition of isatuximab, an anti-CD38 monoclonal antibody, to pomalidomide-dexamethasone (Pd) in patients with relapsed/refractory multiple myeloma. Here, we report the final OS analysis. This multicenter, randomized, open-label, phase 3 study included patients who had received and failed ≥2 previous therapies, including lenalidomide and a proteasome inhibitor. Between January 10, 2017, and February 2, 2018, 307 patients were randomized (1:1) to isatuximab-pomalidomide- dexamethasone (Isa-Pd; n = 154) or Pd (n = 153), stratified based on age (3). At data cutoff for the final OS analysis after 220 OS events (January 27, 2022), median follow-up duration was 52.4 months. Median OS (95% confidence interval) was 24.6 months (20.3-31.3 months) with Isa-Pd and 17.7 months (14.4-26.2 months) with Pd (hazard ratio = 0.78; 95% CI, 0.59-1.02; 1-sided P = 0.0319). Despite subsequent daratumumab use in the Pd group and its potential benefit on PFS in the first subsequent therapy line, median PFS2 was significantly longer with Isa-Pd vs. Pd (17.5 vs. 12.9 months; log-rank 1-sided P = 0.0091). In this analysis, Isa-Pd continued to be efficacious and well tolerated after follow-up of approximately 52 months, contributing to a clinically meaningful, 6.9-month improvement in median overall survival in patients with relapsed/refractory multiple myeloma.
PubMed: 38299578
DOI: 10.3324/haematol.2023.284325 -
Life (Basel, Switzerland) Nov 2023This review discusses immunomodulatory drug (IMiDs) sequencing and IMiD-free interval strategies for lenalidomide-refractory myeloma. IMiDs and proteasome inhibitors... (Review)
Review
This review discusses immunomodulatory drug (IMiDs) sequencing and IMiD-free interval strategies for lenalidomide-refractory myeloma. IMiDs and proteasome inhibitors (PIs) improve clinical outcomes in patients with myeloma; however, refractoriness to lenalidomide, a category of IMiD, predicts poor outcomes. Next-generation IMiDs, such as pomalidomide, are effective even for lenalidomide-refractory myeloma. Therefore, an IMiD-sequencing strategy from lenalidomide to pomalidomide would be desirable. PIs are an antimyeloma therapeutic agent with another mode of action that might restore cereblon, a target of IMiDs; therefore, an IMiD-free interval via class switching from lenalidomide to PIs may be a promising alternative for lenalidomide-refractory myeloma. Additionally, the anti-CD38 monoclonal antibody is a key drug for salvage therapy in anti-CD38 monoclonal antibody-naïve patients. In clinical practice, safety profiles and social convenience can play important roles in the choice of combination therapy. In the future, the selection of optimal treatments should be based on the status of the immunological environment and genetic alterations. This review aims to discuss IMiDs sequencing and IMiD-free interval strategies for lenalidomide- refractory myeloma.
PubMed: 38004369
DOI: 10.3390/life13112229 -
Cancers Oct 2023Daratumumab-based combinations with pomalidomide/dexamethasone (DPd), or bortezomib/dexamethasone (DVd), have shown activity in relapsed/refractory multiple myeloma...
Efficacy and Safety of Daratumumab, Pomalidomide, and Dexamethasone (DPd) Compared to Daratumumab, Bortezomib, and Dexamethasone (DVd) in Daratumumab-Naïve Relapsed Multiple Myeloma.
Daratumumab-based combinations with pomalidomide/dexamethasone (DPd), or bortezomib/dexamethasone (DVd), have shown activity in relapsed/refractory multiple myeloma (RRMM) patients. However, no direct comparisons of safety or efficacy of the two regimens have been published to date. We conducted a retrospective study to compare the safety and efficacy of DPd and DVd in daratumumab-naïve RRMM patients. We included 140 daratumumab-naïve patients who had received DPd or DVd for RRMM. Overall, the DPd group had a greater number of patients who had high-risk disease characteristics. Although response was deeper in the DPd group, the median progression-free survival (PFS) and overall survival (OS) were similar between the two groups. The DPd group exhibited a higher incidence of hematologic toxicities, whereas the DVd group had a higher incidence of peripheral neuropathy. The study results showed that while DPd may provide a deeper response, there was no significant difference in PFS or OS compared to DVd. For the high proportion of difficult-to-treat patients, duration of treatment may have contributed to these results, indicating that patient and disease characteristics should be considered when selecting salvage treatments.
PubMed: 37835587
DOI: 10.3390/cancers15194894 -
Frontiers in Oncology 2023Multiple Myeloma (MM) patients exhibit dysregulated immune system, which is further weakened by chemotherapeutic agents. While cereblon-modulating agents, such as...
Immunomodulation of NK, NKT and B/T cell subtypes in relapsed/refractory multiple myeloma patients treated with pomalidomide along with velcade and dexamethasone and its association with improved progression-free survival.
BACKGROUND
Multiple Myeloma (MM) patients exhibit dysregulated immune system, which is further weakened by chemotherapeutic agents. While cereblon-modulating agents, such as pomalidomide and lenalidomide, have been found to improve the immune profile, the efficacy of their impact in combination with other treatments is yet unknown.
METHODS
We conducted an immune-profiling of a longitudinal cohort of 366 peripheral blood samples from the CC4047-MM-007 (OPTIMISMM, NCT01734928) study. This study followed relapsed/refractory Multiple Myeloma (RRMM) patients who were treated with Velcade + dexamethasone (Vd), or Vd with pomalidomide (PVd). 366 blood samples from 186 patients were evaluated using multi-color flow cytometry at 3 timepoints: screening, day 8 of cycle 1, and cycle 3.
RESULTS
Among NK and NKT cell populations, adding pomalidomide showed no inhibition in the frequency of NK cells. When expression of double positivity for activation markers like, p46/NKG2D, on NK cells was higher than the median, PVd treated patients showed significantly better (p=0.05) progression-free survival (PFS) (additional 15 months) than patients with lower than the median expression of p46/NKG2D on NK cells. PVd treated patients who expressed CD158a/b below the median at cycle 1 demonstrated a significantly better PFS (more than 18months). Among B cell subtypes, PVd treatment significantly increased the abundance of B1b cells (p<0.05) and decreased Bregs (p<0.05) at day 8 of both cycle 1 and cycle 3 when compared to screening samples. Of all the B cell-markers evaluated among paired samples, a higher expression of MZB cells at day 8 of cycle 1 has resulted in enhanced PFS in PVd treated patients. Within T cells, pomalidomide treatment did not decrease the frequency of CD8 T cells when compared with screening samples. The higher the surface expression of OX-40 on CD8 T cells and the lower the expression of PD-1 and CD25 on CD4 T cells by PVd treatment resulted in improved PFS.
CONCLUSION
The prognostic significance for the number of immune markers is only seen in the PVd arm and none of these immune markers exhibit prognostic values in the Vd arm. This study demonstrates the importance of the immunomodulatory effects and the therapeutic benefit of adding pomalidomide to Vd treatment.
PubMed: 38111533
DOI: 10.3389/fonc.2023.1271807 -
Nature Communications Dec 2023Thalidomide and its analogs are molecular glues (MGs) that lead to targeted ubiquitination and degradation of key cancer proteins via the cereblon (CRBN) E3 ligase....
Thalidomide and its analogs are molecular glues (MGs) that lead to targeted ubiquitination and degradation of key cancer proteins via the cereblon (CRBN) E3 ligase. Here, we develop a direct-to-biology (D2B) approach for accelerated discovery of MGs. In this platform, automated, high throughput, and nano scale synthesis of hundreds of pomalidomide-based MGs was combined with rapid phenotypic screening, enabling an unprecedented fast identification of potent CRBN-acting MGs. The small molecules were further validated by degradation profiling and anti-cancer activity. This revealed E14 as a potent MG degrader targeting IKZF1/3, GSPT1 and 2 with profound effects on a panel of cancer cells. In a more generalized view, integration of automated, nanoscale synthesis with phenotypic assays has the potential to accelerate MGs discovery.
Topics: Ubiquitin-Protein Ligases; Peptide Hydrolases; Ubiquitination; Proteolysis; Biology
PubMed: 38114468
DOI: 10.1038/s41467-023-43614-3 -
Clinical Lymphoma, Myeloma & Leukemia Nov 2023The objective was to assess the benefit of pomalidomide-based combination regimens in patients with relapsed/refractory multiple myeloma (RRMM) previously treated with... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
The objective was to assess the benefit of pomalidomide-based combination regimens in patients with relapsed/refractory multiple myeloma (RRMM) previously treated with lenalidomide. A pooled estimate was obtained for efficacy outcomes including overall response rate (ORR), complete response (CR) rate, and progression-free survival (PFS) based on multiple trials conducted in this patient population.
PATIENTS AND METHODS
A literature search was conducted on March 22, 2022 for relevant trials published between January 1, 2016 and the search date. The search identified 12 eligible trials with publications dated between 2016 and 2021. The meta-analyses were conducted among the intention-to-treat (ITT) population (patients treated in all lines of therapy) and 2 subpopulations: 2L (only patients treated in the second line [2L]) and ≥2L (patients treated in the 2L and beyond).
RESULTS
From the meta-analyses, ORR was 69.9% for ITT, 74.4% for ≥2L, and 87.2% for 2L. CR rate was 12.1% for ITT, 17.6% for ≥2L, and 29.7% for 2L. One-year PFS rates were 55.1% for ITT, 59.1% for ≥2L, and 74.0% for 2L. Two-year PFS rates were 29.3% for ITT, 36.0% for ≥2L, and 41.9% for 2L.
CONCLUSION
Pomalidomide-based combination regimens were effective in patients with RRMM previously treated with lenalidomide and tended to be associated with better outcomes when used earlier in the treatment pathway. A drug class switch may not always be necessary when making treatment decisions for patients with RRMM for whom the benefits of lenalidomide have been exhausted, although this must be supported by comparative studies.
Topics: Humans; Antineoplastic Combined Chemotherapy Protocols; Lenalidomide; Multiple Myeloma; Thalidomide
PubMed: 37684184
DOI: 10.1016/j.clml.2023.07.010