Pomalidomide improves the effectiveness of CAR-T treatment in the relapsed and refractory multiple myeloma or B-cell leukemia/lymphoma with extramedullary disease

Relapsed and refractory multiple myeloma (RRMM) and B-cell leukemia/lymphoma with extramedullary disease (EMD) have poor prognosis and high mortality, lack of effective therapeutic approaches. We reported for the first time that 6 patients with malignant hematological diseases with EMD received chimeric antigen receptor (CAR)-T treatment combined with pomalidomide, and CAR-T cells were treated with pomalidomide in vitro to determine its killing activity and cytokine secretion. Three patients with RRMM were given B cell maturation antigen (BCMA)-CAR-T therapy. All 3 patients with B-cell leukemia/lymphoma received CD19/22-CAR-T sequential infusion. There were no treatment-related deaths. The maximum overall response rate (ORR) was 100%. Median follow-up was 211.5 days (75-407 days). Three patients (50%) experienced cytokine release syndrome, all of which were grade 1, and no neurotoxicity was observed. In vitro experiments showed that the killing activity did not differ significantly between BCMA-CAR-T cells with and without pomalidomide (10, 25, or 50 μg/mL) in 8226/U266 cell cocultures (P > .05). Tumor necrosis factor (TNF)-α and interferon (IFN)-γ secretion was significantly higher from 8226 and Raji cells cocultured with BCMA-CAR-T and cluster of differentiation (CD)19-CAR-T cells (P < .05). Based on the cocultures, adding pomalidomide significantly promoted IFN-γ and TNF-α secretion (P < .05). Based on the above clinical and in vitro studies demonstrating the co-administration of pomalidomide with CAR-T cell treatment demonstrated favorable tolerability and therapeutic effectiveness in RRMM or B-cell leukemia/lymphoma.

Cereblon-Targeting Ligase Degraders in Myeloma: Mechanisms of Action and Resistance

Cereblon-targeting degraders, including immunomodulatory imide drugs lenalidomide and pomalidomide alongside cereblon E3 ligase modulators like iberdomide and mezigdomide, have demonstrated significant anti-myeloma effects. These drugs play a crucial role in diverse therapeutic approaches for multiple myeloma (MM), emphasizing their therapeutic importance across various disease stages. Despite their evident efficacy, approximately 5% to 10% of MM patients exhibit primary resistance to lenalidomide, and resistance commonly develops over time. Understanding the intricate mechanisms of action and resistance to this drug class becomes imperative for refining and advancing novel therapeutic combinations.

Efficacy and safety of generic pomalidomide plus low-dose dexamethasone in relapsed or refractory multiple myeloma: a multicenter, open-label, single-arm trial

This multicenter, open-label, single-arm trial (ClinicalTrials.gov, NCT05236621) was conducted to confirm the efficacy and safety of generic pomalidomide plus dexamethasone in Chinese patients with relapsed or refractory multiple myeloma (RRMM). Total 79 eligible RRMM patients were planned to be included. Patients were treated with generic pomalidomide (4 mg daily on days 1-21, orally) and low-dose dexamethasone (40 mg/day on days 1, 8, 15, and 22, orally; 20 mg for patients aged > 75 years) in 28-day cycles until disease progression with a maximum treatment duration of 2 years. The primary endpoint is the overall response rate (ORR) assessed by the independent review committee per the 2016 International Myeloma Working Group guidelines. A total of 85 eligible patients were included in this study from 32 centers in China, with a median age of 62.0 (range, 39-76) years, a median prior line of therapy of 4 (range, 1-16), and 41.2% patients with high-risk cytogenetics. The ORR was 38.8% (95% confidence interval (CI), 28.44-50.01). The disease control rate was 67.1% (95% CI, 56.02-76.87), meanwhile, the median progression-free survival was 5.55 months (95% CI, 3.68-7.52). Among the treatment-related adverse events (TRAEs), infective pneumonia (17.6%) was the most frequent non-hematologic adverse event, while a decrease in neutrophil count (52.9%) was the most common grade ≥ 3 TRAE. The study results indicated that the generic pomalidomide demonstrated consistent efficacy and a safety profile similar to the branded pomalidomide when combined with low-dose dexamethasone in Chinese RRMM patients.Registration number ClinicalTrials.gov NCT05236621, retrospectively registered on February 11, 2022.

Near-infrared light controlled protein degradation by photo-caged lenalidomide and pomalidomide

Immunomodulatory drugs (e.g. thalidomide, lenalidomide and pomalidomide) have been proven highly successful in clinical treatment of multiple myeloma. However, systematic degradation of zinc finger transcriptional factors induced by these drugs could lead to severe systematic toxicity in patients. Previous reports of NVOC caged pomalidomide attempted to regulate its activity using UVA irradiation, but their application was limited by high cytotoxicity and low tissue penetration. Here, we reported red-shifted BODIPY caged lenalidomide and pomalidomide that enabled red-light controlled protein degradation with spatiotemporal precision.

Continuous Elotuzumab, Pomalidomide, and Dexamethasone Maintenance Following Second Autologous Transplantation for Multiple Myeloma: Results of a Prospective Phase 2 Multicenter Trial

Second autologous hematopoietic cell transplantation (AHCT2) is a useful therapeutic modality for fit patients with multiple myeloma who have durable remission after upfront AHCT. Retrospective studies have suggested a significant benefit of incorporating maintenance therapy post-AHCT2, but prospective data on specific regimens are lacking. The purpose of this study was to investigate the use of elotuzumab, pomalidomide, and dexamethasone (EPd) as salvage therapy prior to and maintenance after AHCT2 for relapsed multiple myeloma. This prospective single-arm phase II trial investigating the use of EPd in combination with AHCT2 in patients with relapsed multiple myeloma was conducted at 2 academic centers in North America. The primary outcome was 1-year progression-free survival (PFS). Twenty-five patients were enrolled on the study. Sixteen patients received EPd induction; six patients (38%) progressed during salvage therapy and were removed from the trial prior to AHCT2. Following a planned safety analysis, the protocol was amended, and EPd induction was removed from the study schema. An additional 9 patients underwent induction off-study and were enrolled on trial for AHCT2 and EPd maintenance. A total of 18 patients underwent AHCT2 and received EPd maintenance. Two patients discontinued treatment because of toxicity, one attributed to elotuzumab and the other to pomalidomide. The 1-year PFS was 72%, and the median PFS was 19 months. The study was closed early owing to poor accrual; 6 patients remained on therapy at time of analysis. EPd maintenance after AHCT2 was safe and tolerable. The 1-year PFS and median PFS were similar to values in previous retrospective reports of outcomes following AHCT2. Further studies are needed to define the optimal use of and protocol for AHCT2 in fit patients with relapsed multiple myeloma.

[Bendamustine combined with pomalidomide and dexamethasone in relapsed multiple myeloma with extramedullary disease: a multicenter study]

Objective: To evaluate the efficacy and safety of bendamustine combined with pomalidomide and dexamethasone (BPD regimen) in the treatment of relapsed multiple myeloma (MM) with extramedullary disease. Methods: This open, single-arm, multicenter prospective cohort study included 30 relapsed MM patients with extramedullary disease diagnosed in seven hospitals including Qingdao Municipal Hospital. The patients were treated with BPD regimen from February 2021 to November 2022. This study analyzed the efficacy and adverse reactions of the BPD regimen. Results: The median age of the 30 patients was 62 (47-72) years, of which 18 (60% ) had first-time recurrence. The overall response rate (ORR) of the 18 patients with first-time recurrence was 100%, of which three (16.7% ) achieved complete remission, 10 (55.5% ) achieved very good partial remission (VGPR), and five (27.8% ) achieved partial remission (PR). The ORR of 12 patients with recurrence after second-line or above treatment was 50%, including zero patients with ≥VGPR and six patients (50% ) with PR. Three cases (25% ) had stable disease, and three cases (25% ) had disease progression. The one-year progression free survival rate of all patients was 65.2% (95% CI 37.2% -83.1% ), and the 1-year overall survival rate was 90.0% (95% CI 76.2% -95.4% ). The common grade 3-4 hematology adverse reactions included two cases (6.7% ) of neutropenia and one case (3.3% ) of thrombocytopenia. The overall adverse reactions are controllable. Conclusions: The BPD regimen has good efficacy and tolerance in relapsed MM patients with extramedullary disease.

Pomalidomide combinations are a safe and effective option after daratumumab failure

PURPOSE

Outcomes of multiple myeloma (MM) patients who are refractory to daratumumab are dismal and no standard of treatment exists for this patients' population. Here, we investigate the role of pomalidomide combinations in daratumumab-refractory MM patients.

METHODS

We performed a retrospective analysis of myeloma patients treated at four referral centers (three in Germany and one in Italy). Review chart identified 30 patients with relapsed and refractory myeloma, who progressed during treatment with daratumumab and were treated with pomalidomide-based combinations in the subsequent lines of therapy.

RESULTS

Responses improved from 37% with daratumumab to 53% with pomalidomide. Of seven patients with extramedullary MM (EMM), four achieved a clinical stabilization with pomalidomide, including one patient with a long-lasting complete response. Median progression-free survival and overall survival were 6 and 12 months, respectively. Pomalidomide combinations were well tolerated, no patient discontinued treatment due to adverse events.

CONCLUSION

These data show that pomalidomide-based combinations can be an effective and safe salvage regimen for daratumumab-refractory patients, including those with EMM.

Evidence-based mechanisms of synergy with IMiD agent-based combinations in multiple myeloma

Treatment of multiple myeloma (MM) has seen great advances in recent years, and a key contributor to this change has been the effective use of combination therapies, which have improved both the depth and duration of patient responses. IMiD agents (lenalidomide and pomalidomide) have both tumoricidal and immunostimulatory functions, and due to their multiple mechanisms of action have become the backbone of numerous combination treatments in the newly diagnosed and relapsed/refractory settings. Although IMiD agent-based combination regimens provide improved clinical outcomes for patients with MM, the mechanisms underpinning these combinations are not well understood. In this review we describe the potential mechanisms of synergy leading to the enhanced activity observed when IMiD agents and other drug classes are used in combination through interrogation of the current knowledge surrounding their mechanism of actions.

Assessment of Time-to-onset and Outcome of Lung Adverse Events With Pomalidomide from a Pharmacovigilance Study

BACKGROUND/AIM

Pomalidomide is an immunomodulatory drug that is used to treat multiple myeloma. We examined the time-to-onset and outcome of lung adverse events (LAEs) related to pomalidomide in Japanese patients based on information obtained from the spontaneous reporting system of the Japanese Adverse Drug Event Report database (JADER) of the Pharmaceuticals and Medical Devices Agency.

PATIENTS AND METHODS

We analyzed adverse events (AEs) reports recorded between April 2004 and March 2021 from JADER. Data on LAEs were extracted, and the relative risk of AEs was estimated using the reporting odds ratio and 95% confidence interval. We analyzed 1,772,494 reports and identified 2,918 reports of AEs caused by pomalidomide. Of these, 253 LAEs were reportedly associated with pomalidomide.

RESULTS

Signals were detected for five LAEs: pneumonia, pneumocystis jirovecii pneumonia, bronchitis, pneumonia bacterial, and pneumonia pneumococcal. Pneumonia was the most frequently mentioned condition (68.8%). The median time-to-onset of pneumonia was 66 days, but some cases of pneumonia occurred as late as 20 months after the start of administration. Fatal outcomes were observed in two of the five AEs wherein signals were detected and were due to pneumonia and bacterial pneumonia.

CONCLUSION

Serious outcomes can occur after pomalidomide administration. It has been suggested that these LAEs occur relatively early after pomalidomide administration. Since some situations can result in fatal consequences, patients should be monitored for the emergence of these AEs over a prolonged period of time, especially for pneumonia.

Pharmacokinetics and bioequivalence of two pomalidomide capsules in healthy chinese subjects under fasting and fed conditions

OBJECTIVE

Imnovid® is an immunomodulatory drug with antineoplastic activity. The aim of this study was to evaluate the bioequivalence and safety of the generic drug pomalidomide (Chia Tai Tianqing Pharmaceutical Group Co., Ltd) and its originator product Imnovid® (Celgene Europe Ltd) in the fasting and fed states, respectively.

METHODS

The research consisted of two parts: one with a dose of 1 mg and the other with a dose of 4 mg. 48 healthy subjects were included in each study and were divided into two groups (fasting group and fed group) at a 1:1 ratio to administrate study drugs orally. The plasma drug concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

The 90% CI of GMR for main pharmacokinetic (PK) parameters (C_max, AUC_0 - t and AUC_0-∞) met the requirements of bioequivalence standards. The incidence and severity of AEs associated with pomalidomide and Imnovid® were similar.

CONCLUSION

The results proved the PK parameters of pomalidomide and Imnovid® were similar and bioequivalent. Both drugs showed safety profile well.

Adverse Hematological and Non-Hematological Events in Patients With Relapsed/Refractory Multiple Myeloma That Are Responsive to Daratumumab, Pomalidomide and Dexamethasone

Background

Daratumumab, pomalidomide, and dexamethasone (DPd) is an effective option for treatment of patients with relapsed/refractory multiple myeloma (RRMM). In this study, we sought to analyze the risk of hematological and non-hematological toxicities in patients who responded to DPd treatment.

Methods

We analyzed 97 patients with RRMM who were treated with DPd between January 2015 and June 2022. The patients and disease characteristics, as well as safety and efficacy outcomes were summarized as descriptive analysis.

Results

The overall response rate for the entire group was 74% (n = 72). The most common grade III/IV hematological toxicities in those who responded to treatment were neutropenia (79%), leukopenia (65%), lymphopenia (56%), anemia (18%), and thrombocytopenia (8%). The most common grade III/IV non-hematological toxicities were pneumonia (17%) and peripheral neuropathy (8%). The incidence of dose reduction/interruption was 76% (55/72), which was due to hematological toxicity in 73% of the cases. The most common reason for discontinuing treatment was disease progression in 61% (44 out of 72 patients).

Conclusions

Our study revealed that patients who respond to DPd are at high risk of dose reduction or treatment interruption because of hematological toxicity, typically due to neutropenia and leukopenia leading to increased risk of hospitalization and pneumonia.

Repurposing Thalidomide, Its Analogue And Apremilast For Possible Antiviral In Situation Of Severe Covid Cytokine Syndrome

BACKGROUND

COVID-19, caused by SARS-corona virus-2, is a global wide expanded public health risk at a bizarre level. In this current situation, COVID-19 became a serious emerging pandemic. Choosing drug reusing is a crucial step in identifying the new uses of old established drugs. To achieve a significant and healthy way of treatment in COVID patients within a short duration, drug repurposing is a novel method.

OBJECTIVE

The present study concentrated on the molecular docking of thalidomide and its analogues and Apremilast against Coronavirus infectious symptoms, evaluated on virus proteins (Spike Protein, 3cl Protease, Nucleocapsids).

METHODS

The present study explores the possibility of repurposing thalidomide for the treatment of SARS-COV-2 infection by assessing and confirming with docking affinity scores of thalidomide & its analogues and Apremilast, with spike protein, 3cl protease, and nucleocapsids.

RESULTS

From the study results, thalidomide, pomalidomide, lenalidomide, and Apremilast exhibited better binding affinity to N Protein (4KXJ), Protease (4WY3) and Spike Protein (5WRG). In comparison of targets, N Protein - 4KXJ is the best for the four ligands. It is finalized that all four ligands (Thalidomide - -8.6, Pomalidomide - -8.8, Lenalidomide,and - -8.2,and Apremilast - -8.1) have good docking scores with the target N Protein.

CONCLUSION

The present study shows confirmation that thalidomide and its analogues and apremilast as a better fit for treating high risk patients of COVID -19 viral infection which are supposed to promote beneficial effects for both respiratory illnesses like COVID-19 symptoms as well as improve the pathological state of condition.

Nanocrystals as an effective strategy to improve Pomalidomide bioavailability in rodent

Pomalidomide (POM) is an FDA-approved immunomodulatory imide drug (IMiDs) an it is effectively used in the treatment of multiple myeloma. IMiDs are analogs of the drug thalidomide and they have been repurposed for the treatment of several diseases such as psoriatic arthritis and Kaposi Sarcoma. In recent years, IMiDs have been also evaluated as a new treatment for neurological disorders with an inflammatory and neuroinflammatory component. POM draws particular interest for its potent anti-TNF-α activity at significantly lower concentrations than the parent compound thalidomide. However, POM's low water solubility underpins its low gastrointestinal permeability resulting in irregular and poor absorption. The purpose of this work was to prepare a POM nanocrystal-based formulation that could efficiently improve POM's plasma and brain concentration after intraperitoneal injection. POM nanocrystals prepared as a nanosuspension by the media milling method showed a mean diameter of 219 nm and a polydispersity index of 0.21. POM's nanocrystal solubility value (22.97 µg/mL) in phosphate buffer was about 1.58 folds higher than the POM raw powder. Finally, in vivo studies conducted in adult Male Sprague-Dawley rats indicated that POM nanocrystal ensured higher and longer-lasting drug levels in plasma and brain when compared with POM coarse suspension.

Treatment Options for Patients With Heavily Pretreated Relapsed and Refractory Multiple Myeloma

Despite the increasing number of treatment options available for multiple myeloma, relapse is still inevitable and there remains a critical unmet need for treatments for patients with late-stage, highly refractory disease. In this review, we discuss currently approved treatment options for heavily pretreated patients with relapsed and refractory multiple myeloma, with a focus on the optimal management of patients with MM refractory to lenalidomide, bortezomib, and in some cases, daratumumab or an anti-CD38 monoclonal antibody. Data from recent clinical trials of immunomodulatory agents (pomalidomide), proteasome inhibitors (PIs; carfilzomib and ixazomib), monoclonal antibodies (elotuzumab, daratumumab, and isatuximab), and other novel therapies (including panobinostat-based therapy) are summarized. We also provide potential therapeutic strategies for patients according to different treatment histories, and include case studies to illustrate the practical use of various treatment options in a clinical setting. Regimens containing pomalidomide, elotuzumab, next-generation PIs, panobinostat, or selinexor may provide effective treatment options in patients with triple-refractory disease. The choice of agents used, and combinations thereof should be individualized as well as strategically planned from early- to late-stage relapse.

Efficacy and safety of pomalidomide and low-dose dexamethasone in Chinese patients with relapsed or refractory multiple myeloma: a multicenter, prospective, single-arm, phase 2 trial

Background

Pomalidomide in combination with dexamethasone has demonstrated positive results in patients with relapsed or refractory multiple myeloma (RRMM), but no data are available in China. We conducted a multicenter, single-arm trial to examine the efficacy and safety of bioequivalent generic pomalidomide plus low-dose dexamethasone in Chinese RRMM patients.

Methods

Adult (≥ 18 years of age) RRMM patients who progressed after at least two previous treatments, including bortezomib and lenalidomide, were eligible. Pomalidomide was given orally at 4 mg/day on days 1 to 21 of a 28-day cycle. Dexamethasone was given at 40 mg/day (either orally or intravenously; 20 mg/day at 75 years or older) on days 1, 8, 15, and 22 of each cycle. Treatment continued until disease progression or intolerable adverse events (AEs). The primary end point was objective response rate (ORR).

Results

Seventy-four patients were enrolled between February 2017 and February 2019. All patients had progressed within 60 days of their last therapy. 74.3% of the patients were resistant to lenalidomide, 31.1% had renal insufficiency and 33.8% had high-risk cytogenetic RRMM. The median follow-up duration was 33.0 months (range 31.1–34.8 months). The ORR was 37.8% in the overall analysis, 32.7% in lenalidomide-refractory patients, 36.0% in patients with high-risk cytogenetics and 34.8% in RRMM patients with renal impairment. The median progression-free survival was 5.7 months (95% CI 3.7–8.8 months). The median overall survival was 24.3 months (95% CI 14.4–41.1 months). The most common grade 3 and 4 treatment-emergent adverse events (TEAEs) were neutropenia (63.5%), leukopenia (37.8%), thrombocytopenia (28.4%), and anemia (31.1%). Pulmonary infection (27.0%) was the most frequent grade 3 and 4 nonhematologic TEAE. No previously unreported AEs were observed. No venous thromboembolism was reported.

Conclusions

Pomalidomide in combination with low-dose dexamethasone is effective and safe in Chinese RRMM patients.

Trial registration

The study is registered at Chinese Clinical Trial Registry (ChiCTR) (ChiCTR-OIC-17013234, first registered on 03/11/2017).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09802-y.

Low cerebrospinal fluid-to-plasma ratios of orally administered lenalidomide mediated by its low cell membrane permeability in patients with hematologic malignancies

Lenalidomide is a synthetic analog of thalidomide formed by the removal of one keto group (plus the addition of an amino group); it has anti-tumor activities beneficial for the treatment of hematologic malignancies. However, lenalidomide distribution to brain in animal models is reportedly low compared with that of thalidomide. The aim of this study was to evaluate plasma and cerebrospinal fluid concentrations of lenalidomide in three patients with malignant hematologic malignancies. Lenalidomide was detected in plasma from the three Japanese patients 1.5 h following oral administration of 20 mg lenalidomide using liquid chromatography/mass spectrometry, despite the in vitro gastrointestinal permeability of lenalidomide being low. Clinically observed cerebrospinal fluid-to-plasma ratios of lenalidomide were low (1.3-2.4%). Observed influx permeability values for lenalidomide in monkey blood-brain barrier model and human placental cell systems were one order of magnitude lower than those of thalidomide and another second-generation drug, pomalidomide along with a positive permeability control, caffeine. Because of the low cell-barrier permeability of lenalidomide demonstrated in in vitro assays, clinically relevant pharmacokinetic profiles of lenalidomide resulted in low penetrability from plasma into cerebrospinal fluid in patients with hematologic malignancies. Lenalidomide is conclusively suggested to expert its favorable immunomodulatory effects via systemic exposures in the patients.

Discovery of pomalidomide-based PROTACs for selective degradation of histone deacetylase 8

Overexpression of histone deacetylase 8 (HDAC8) is associated with various diseases such as cancer. Thus, compounds that can modulate HDAC8 levels have therapeutic potential for these diseases. Based on the proteolysis targeting chimera (PROTAC) strategy, we designed and synthesized a series of HDAC8 degraders by tethering an HDAC6/8 dual inhibitor with pomalidomide (a cereblon ligand). Among them, compound ZQ-23 exhibited significant and selective degradation of HDAC8 with DC₅₀ of 147 nM and D_max of 93%, and exhibited no effects on HDAC1 and HDAC3. Interestingly, we found that the degradation of target protein started at ∼2 h after treatment with ZQ-23 and the maximal degradation effect was achieved at 10 h. The HDAC8 level was partially recovered within 24 h. In addition, ZQ-23 had no degrading effects on HDAC1 and HDAC3 at all concentrations, but could dose-dependently increase the levels of acetylated SMC-3 (HDAC8 substrate). Mechanism study demonstrated that ZQ-23 degraded HDAC8 through the ubiquitin-protease pathway, rather than lysosome system. Collectively, these results suggest that ZQ-23 represents a novel PROTAC-based HDAC8 degrader worthy of further investigation.

Pomalidomide, dexamethasone, and daratumumab immediately after lenalidomide-based treatment in patients with multiple myeloma: updated efficacy, safety, and health-related quality of life results from the phase 2 MM-014 trial

Patients with relapsed/refractory multiple myeloma (RRMM) need proven subsequent therapies after early-line lenalidomide treatment failure. The phase 2 MM-014 trial (NCT01946477) investigated pomalidomide, dexamethasone, and daratumumab after 1 to 2 prior treatment lines (62.5%, 1 prior line) in patients with RRMM and prior lenalidomide (75.0%, lenalidomide refractory). With a median follow-up of 28.4 months, overall response rate was 77.7% (52.7% achieved very good partial response or better) and median progression-free survival was 30.8 months. For patients with lenalidomide-refractory disease, these outcomes were 76.2%, 47.6%, and 23.7 months, respectively. No new safety signals were observed; 64.3% experienced grade 3/4 neutropenia. Health-related quality of life was preserved or trended toward improvement through 12 treatment cycles. Pomalidomide, dexamethasone, and daratumumab given immediately after early-line lenalidomide-based treatment continues to demonstrate safety and efficacy, supporting pomalidomide-dexamethasone as a foundation of combination therapy in RRMM and providing evidence that the immunomodulatory agent class delivers benefit after lenalidomide treatment failure.

Isatuximab plus Pomalidomide and Dexamethasone in a Patient with Dialysis-Dependent Multiple Myeloma

The phase 3 ICARIA-MM trial showed that the addition of isatuximab improved the progression-free survival compared with pomalidomide/dexamethasone. However, the safety and efficacy of isatuximab for end-stage renal failure remains unclear. A 67-year-old man who started hemodialysis 5 years ago for diabetic nephropathy was diagnosed with International Staging System stage III multiple myeloma (MM) of IgD-λ type 3 years ago. After receiving a total of 7 treatment regimens, his free light chain (FLC) λ level increased from 419 to 2,070 mg/L, indicating progressive disease. Twelve days after starting isatuximab plus pomalidomide (3 mg daily) and dexamethasone (IsaPd), his FLC λ level rapidly decreased to 412 mg/L. The patient has now completed 7 courses of IsaPd with no adverse events, including infusion reactions and neutropenia. Isatuximab requires a lower dilution volume than daratumumab and can be safely and effectively administered to hemodialysis-dependent MM patients.

Synthesis and pharmacological evaluation of pomalidomide derivatives useful for sickle cell disease treatment

Fetal hemoglobin (HbF) induction constitutes a valuable and validated approach to treat the symptoms of sickle cell disease (SCD). Here, we synthesized pomalidomide-nitric oxide (NO) donor derivatives (3a-f) and evaluated their suitability as novel HbF inducers. All compounds demonstrated different capacities of releasing NO, ranging 0.3-30.3%. Compound 3d was the most effective HbF inducer for CD34+ cells, exhibiting an effect similar to that of hydroxyurea. We investigated the mode of action of compound 3d for HbF induction by studying the in vitro alterations in the levels of transcription factors (BCL11A, IKAROS, and LRF), inhibition of histone deacetylase enzymes (HDAC-1 and HDAC-2), and measurement of cGMP levels. Additionally, compound 3d exhibited a potent anti-inflammatory effect similar to that of pomalidomide by reducing the TNF-α levels in human mononuclear cells treated with lipopolysaccharides up to 58.6%. Chemical hydrolysis studies revealed that compound 3d was stable at pH 7.4 up to 24 h. These results suggest that compound 3d is a novel HbF inducer prototype with the potential to treat SCD symptoms.

Implementation of a Pregnancy Prevention Programme (PPP) with a Controlled Distribution System (CDS) for the Generic Teratogenic Phthalimides Thalidomide, Lenalidomide and Pomalidomide

Thalidomide (α-phthalimidoglutaride) was marketed in the 1950s and early 1960s; it was promoted as a sedative-hypnotic agent with minimal hangover. It was available in some countries as an over-the-counter medicine. Publications reporting profound teratogenic effects with thalidomide brought about major revisions to the monitoring of the safety of medicines. As a consequence of previously unrecognised teratogenic effects, it has been estimated that over 12,000 children were born with a range of defects and disabilities, including severe congenital anomalies. Notably, it has been hypothesised that around 40% of babies with thalidomide-induced malformations born during the 1950s and 1960s died in the neonatal period. The commonest causes of death were atresia of the small bowel, cardiac or renal malformations. Nevertheless, phocomelia (as a typical manifestation of thalidomide´s teratogenic effects) has been reported once again after thalidomide was approved for use in areas where leprosy is endemic. As a result, thalidomide embryopathy remains an important topic in countries such as Brazil. Nowadays thalidomide is approved around the world for the treatment of a wide range of conditions, including leprosy, Crohn's disease, multiple myeloma, and certain malignant solid tumours. Second-generation immunmodulatory drugs including lenalidomide and pomalidomide have received approval for use in the management of various forms of neoplastic disease. Based on clinical experience with thalidomide and its derivatives, learnings have been transferred to further research on a subset of substituted phthalimides each of which has a high risk of causing teratogenic effects. This group of phthalimides is classified within regulatory science as human teratogens. In order to gain approval, a Pregnancy Prevention Programme (PPP), along with a Controlled Distribution System (CDS) is required. The challenges of PPPs in particular for a generic manufacturer have been described, including Raising of awareness, and education; Special aspects of data collection and evaluation; Ethically and socially relevant aspects, and Utilising existing information technology and infrastructure. This paper highlights the risks of unplanned pregnancies, provides information on the regulatory background, and regulatory expectations. Our aim is to provide insights and practical learnings that have impacted operational risk management with the teratogenic phthalimides. Opportunities are presented that may support the implementation of harmonised approaches for PPP and CDS using existing IT-systems across countries and companies.

Inclusion complexation of the anticancer drug pomalidomide with cyclodextrins: fast dissolution and improved solubility

Pomalidomide (POM), a potent anticancer thalidomide analogue was characterized in terms of cyclodextrin complexation to improve its aqueous solubility and maintain its anti-angiogenic activity. The most promising cyclodextrin derivatives were selected by phase-solubility studies. From the investigated nine cyclodextrins - differing in cavity size, nature of substituents, degree of substitution and charge - the highest solubility increase was observed with sulfobutylether-β-cyclodextrin (SBE-β-CD). The inclusion complexation between POM and SBE-β-CD was further characterized with a wide variety of state-of-the-art analytical techniques, such as nuclear magnetic resonance spectroscopy (NMR), infrared spectroscopy (IR), circular dichroism spectroscopy, fluorescence spectroscopy as well as X-ray powder diffraction method (XRD). Job plot titration by NMR and the A_L-type phase-solubility diagram indicated 1:1 stoichiometry in a liquid state. Complementary analytical methods were employed for the determination of the stability constant of the complex; the advantages and disadvantages of the different approaches are also discussed. Inclusion complex formation was also assessed by molecular modelling study. Solid state complexation in a 1:1 M ratio was carried out by lyophilization and investigated by IR and XRD. The complex exhibited fast-dissolution with immediate release of POM, when compared to the pure drug at acidic and neutral pH. Kinetic analysis of POM release from lyophilized complex shows that Korsmeyer-Peppas and Weibull model described the best the dissolution kinetics. The cytotoxicity of the complex was tested against the LP-1 human myeloma cell line which revealed that supramolecular interactions did not significantly affect the anti-cancer activity of the drug. Overall, our results suggest that the inclusion complexation of POM with SBE-β-CD could be a promising approach for developing more effective POM formulations with increased solubility.

EMA Review of Isatuximab in Combination with Pomalidomide and Dexamethasone for the Treatment of Adult Patients with Relapsed and Refractory Multiple Myeloma

Isatuximab is a monoclonal antibody that binds to the human CD38 antigen. On May 30, 2020, a marketing authorization valid through the European Union (EU) was issued for isatuximab in combination with pomalidomide and dexamethasone (IsaPd) for the treatment of adult patients with relapsed and refractory (RR) multiple myeloma (MM). The recommended dose of isatuximab was 10 mg/kg, administered intravenously weekly at cycle 1 and then biweekly in subsequent 28-day cycles. Isatuximab was evaluated in a phase III, open-label, multicenter, randomized trial that randomly allocated IsaPd versus pomalidomide plus dexamethasone (Pd) to adult patients with RR MM. The primary endpoint of the trial was progression-free survival, as assessed by an independent review committee, which was superior for the IsaPd arm (hazard ratio, 0.596; 95% confidence interval, 0.436-0.814; p = .001) compared with the Pd arm. Treatment with IsaPd led to higher incidences of treatment-related adverse events (AEs), grade ≥ 3 AEs, and serious AEs compared with Pd treatment. Most frequently observed AEs that occurred more often in the IsaPd arm were infusion-related reactions, infections, respiratory AEs, neutropenia (including neutropenic complications), and thrombocytopenia. The aim of this article is to summarize the scientific review of the application leading to regulatory approval in the EU. IMPLICATIONS FOR PRACTICE: Isatuximab was approved in the European Union, in combination with pomalidomide and dexamethasone, for the treatment of patients with multiple myeloma who have already received therapy but whose disease did not respond or relapsed afterward. The addition of isatuximab resulted in a clinically meaningful and significant prolongation of the time from treatment initiation to further disease relapse or patient's death. The safety profile was considered acceptable, and the benefit-risk ratio was determined to be positive.

Lenalidomide and pomalidomide inhibit growth of prostate stromal cells and human prostate smooth muscle contraction

AIMS

Medical treatment for lower urinary tract symptoms secondary to benign prostatic hyperplasia is characterized by an unfavorable balance between limited efficacy and pronounced side effects. We recently reported, that thalidomide reduces prostate smooth muscle contraction and inhibits cell growth. Like thalidomide, its analogs lenalidomide and pomalidomide are also in clinical use. Therefore, we investigated the effects of lenalidomide and pomalidomide on human prostate smooth muscle contraction, cytoskeletal organization, and growth-related functions in stromal cells.

MATERIALS AND METHODS

Proliferation was assessed by EdU assay and colony formation, cytoskeletal organization by phalloidin staining, cell viability by CCK8, and apoptosis and cell death by flow cytometry in cultured prostate stromal cells (WPMY-1). Contractions of human prostate tissues from radical prostatectomy were induced by methoxamine, noradrenaline, phenylephrine, endothelin-1, U46619, or electric field stimulation (EFS) in an organ bath.

KEY FINDINGS

Proliferation of WPMY-1 cells was significantly reduced by lenalidomide (5-200 μM) and pomalidomide (2.5-5 μM). In parallel, organization of actin filaments collapsed after treatment with lenalidomide and pomalidomide. Lenalidomide and pomalidomide inhibited both adrenergic contractions and non-adrenergic contractions as well as neurogenic contractions induced by EFS. Neither reduction in viability, nor increase in cell death or apoptosis was observed in WPMY-1 cells.

SIGNIFICANCE

Thalidomide-derivatives impair growth of human prostate stromal cells, without showing a decrease in cell viability and, in parallel, inhibit adrenergic, neurogenic, and non-adrenergic contractions by breakdown of the actin cytoskeleton. Urodynamic effects in vivo appear possible.

Real-world comparative effectiveness of triplets containing bortezomib (B), carfilzomib (C), daratumumab (D), or ixazomib (I) in relapsed/refractory multiple myeloma (RRMM) in the US

Multiple available combinations of proteasome inhibitors, immunomodulators (IMIDs), and monoclonal antibodies are shifting the relapsed/refractory multiple myeloma (RRMM) treatment landscape. Lack of head-to-head trials of triplet regimens highlights the need for real-world (RW) evidence. We conducted an RW comparative effectiveness analysis of bortezomib (V), carfilzomib (K), ixazomib (I), and daratumumab (D) combined with either lenalidomide or pomalidomide plus dexamethasone (Rd or Pd) in RRMM. A retrospective cohort of patients initiating triplet regimens in line of therapy (LOT) ≥ 2 on/after 1/1/2014 was followed between 1/2007 and 3/2018 in Optum's deidentified US electronic health records database. Time to next treatment (TTNT) was estimated using Kaplan-Meier methods; regimens were compared using covariate-adjusted Cox proportional hazard models. Seven hundred forty-one patients (820 patient LOTs) with an Rd backbone (VRd, n = 349; KRd, n = 218; DRd, n = 99; IRd, n = 154) and 348 patients (392 patient LOTs) with a Pd backbone (VPd, n = 52; KPd, n = 146; DPd, n = 149; IPd, n = 45) in LOTs ≥2 were identified. More patients ≥75 years received IRd (39.6%), IPd (37.8%), and VRd (36.7%) than other triplets. More patients receiving VRd/VPd were in LOT2 vs other triplets. Unadjusted median TTNT in LOT ≥ 2: VRd, 13.9; KRd, 8.7; IRd, 11.4; DRd, not estimable (NE); and VPd, 12.0; KPd, 6.7; IPd, 9.5 months; DPd, NE. In covariate-adjusted analysis, only KRd vs DRd was associated with a significantly higher risk of next LOT initiation/death (HR 1.72; P = 0.0142); no Pd triplet was significantly different vs DPd in LOT ≥ 2. Our data highlight important efficacy/effectiveness gaps between results observed in phase 3 clinical trials and those realized in the RW.

Pomalidomide, Cyclophosphamide, and Dexamethasone for the Treatment of Relapsed/Refractory Multiple Myeloma: Real-World Analysis of the Pethema-GEM Experience

INTRODUCTION

Treatment of relapsed/refractory multiple myeloma (RRMM) is highly challenging, especially for patients with disease refractory to initial therapy, and in particular for disease developing refractoriness to lenalidomide. Indeed, with currently approved treatments, median progression-free survival (PFS) in the lenalidomide-refractory setting is less than 10 months, reflecting the difficulty in treating this patient population. Pomalidomide is a second-generation immunomodulatory drug that has shown activity in lenalidomide-refractory disease in the setting of different combinations.

PATIENTS AND METHODS

A real-world study was conducted by the Spanish Myeloma group in a cohort of patients with RRMM treated with pomalidomide, cyclophosphamide, and dexamethasone (PomCiDex). One hundred patients were treated with a median of 3 prior lines of therapy.

RESULTS

Overall response rate was 39%, with a clinical benefit rate of 93%. Median PFS was 7.6 months; median overall survival (OS) was 12.6 months. Median PFS and OS survival were consistent across the different subgroups analyzed. Prolonged PFS and OS were found in patients with responsive disease.

CONCLUSION

Our results compared favorably with those obtained with different pomalidomide-based combinations in a similar patient population. PomCiDex remains a manageable, cost-effective, and all-oral triplet combination for RRMM patients.

Protein Ligand Interactions Using Surface Plasmon Resonance

Surface Plasmon Resonance (SPR) is a powerful biophysical method for characterizing small molecule binding to proteins. Owing to its ability to characterize binary inteactions between warheads and E3 ligases or substrates, SPR is a useful tool for the development of targeted protein degraders. SPR is also an effective method for optimizing linkers and characterizing ternary complex interactions that are mediated by heterobifunctional ligands (Roy et al. ACS Chem Biol 14:361-368, 2019). Recent advances in the throughput of modern instruments have improved the ability of SPR to rapidly triage ligands based on binding kinetics and affinity, making this technique invaluable for driving degrader optimization. This chapter describes the characterization of ligands binding to the Thalidomide Binding Domain of mouse Cereblon (mCRBN-TBD) using the Biacore 8K+.

Induced protein degradation of histone deacetylases 3 (HDAC3) by proteolysis targeting chimera (PROTAC)

Histone deacetylases (HDACs) play important roles in inflammatory diseases like asthma and chronic obstructive pulmonary disease (COPD). Unravelling of and interfering with the functions of specific isoenzymes contributing to inflammation provides opportunities for drug development. Here we synthesize proteolysis targeting chimeras (PROTACs) for degradation of class I HDACs in which o-aminoanilide-based class I HDAC inhibitors are tethered to the cereblon ligand pomalidomide. One of these PROTACs, denoted HD-TAC7, showed promising degradation effects for HDAC3 with a DC₅₀ value of 0.32 μM. In contrast to biochemical evidence using siRNA, HD-TAC7 showed a minimal effect on gene expression in LPS/IFNγ-stimulated RAW 264.7 macrophages. The lack of effect can be attributed to downregulation of the NF-κB subunit p65, which is a known side effect of pomalidomide treatment. Altogether, we describe a novel PROTAC that enables selective downregulation of HDAC3 levels, however we note that concomitant downregulation of the NF-κB subunit p65 can confound the biological outcome.

Elotuzumab, pomalidomide, and dexamethasone is a very well tolerated regimen associated with durable remission even in very advanced myeloma: a retrospective study from two academic centers

Background

The anti-SLAMF7 monoclonal antibody, elotuzumab (elo), plus lenalidomide (len) and dexamethasone (dex) is approved for relapsed/refractory MM in the U.S. and Europe. Recently, a small phase 2 study demonstrated an advantage in progression-free survival (PFS) for elo plus pomalidomide (pom)/dex compared to pom/dex alone and resulted in licensing of this novel triplet combination, but clinical experience is still limited.

Purpose

To analyze the efficacy and safety of elo/pom/dex in a “real world” cohort of patients with advanced MM, we queried the databases of the university hospitals of Würzburg and Vienna.

Findings

We identified 22 patients with a median number of five prior lines of therapy who received elo/pom/dex prior to licensing within an early access program. Patients received a median number of 5 four-week treatment cycles. Median PFS was 6.4 months with 12-month and 18-month PFS rates of 35% and 28%, respectively. The overall response rate was 50% and 64% of responding patients who achieved a longer PFS with elo/pom/dex compared to their most recent line of therapy. Objective responses were also seen in five patients who had been pretreated with pomalidomide. Low tumor burden was associated with improved PFS (13.5 months for patients with ISS stage I/II at study entry v 6.4 months for ISS III), although this difference did not reach statistical significance. No infusion-related reactions were reported. The most frequent grade 3/4 adverse events were neutropenia and pneumonia.

Conclusion

Elo/pom/dex is an active and well-tolerated regimen in highly advanced MM even after pretreatment with pomalidomide.

Potent anti-myeloma efficacy of dendritic cell therapy in combination with pomalidomide and programmed death-ligand 1 blockade in a preclinical model of multiple myeloma

Dendritic cell (DC)-based vaccines are recognized as a promising immunotherapeutic strategy against cancer; however, the efficacy of immunotherapy with DCs is controlled via immune checkpoints, such as programmed death-ligand 1 (PD-L1). PD-L1 expressed on DC and tumor cells binds to programmed death-1 (PD-1) receptors on the activated T cells, which leads to the inhibition of cytotoxic T cells. Blocking of PD-L1 on DC may lead to improve the efficacy of DC therapy for cancer. Here we demonstrated that DC vaccination in combination with pomalidomide and programmed death-ligand 1 (PD-L1) blockade inhibited tumor growth of a multiple myeloma (MM) mouse model. DCs + pomalidomide with dexamethasone + PD-L1 blockade significantly inhibited immune immunosuppressive factors and promoted proportions of immune effector cells in the spleen and tumor microenvironment. Additionally, functional activities of cytotoxic T lymphocytes and NK cells in spleen were enhanced by DCs + pomalidomide with dexamethasone + PD-L1 blockade. Taken together, this study identifies a potential new therapeutic approach for the treatment of MM. These results also provide a foundation for the future development of immunotherapeutic modalities to inhibit tumor growth and restore immune function in MM.

UNC0638 induces high levels of fetal hemoglobin expression in β-thalassemia/HbE erythroid progenitor cells

Increased expression of fetal hemoglobin (HbF) improves the clinical severity of β-thalassemia patients. EHMT1/2 histone methyltransferases are epigenetic modifying enzymes that are responsible for catalyzing addition of the repressive histone mark H3K9me2 at silenced genes, including the γ-globin genes. UNC0638, a chemical inhibitor of EHMT1/2, has been shown to induce HbF expression in human erythroid progenitor cell cultures. Here, we report the HbF-inducing activity of UNC0638 in erythroid progenitor cells from β-thalassemia/HbE patients. UNC0638 treatment led to significant increases in γ-globin mRNA, HbF expression, and HbF-containing cells in the absence of significant cytotoxicity. Moreover, UNC0638 showed additive effects on HbF induction in combination with the immunomodulatory drug pomalidomide and the DNMT1 inhibitor decitabine. These studies provide a scientific proof of concept that a small molecule targeting EHMT1/2 epigenetic enzymes, used alone or in combination with pomalidomide or decitabine, is a potential therapeutic approach for HbF induction. Further development of structural analogs of UNC0638 with similar biological effects but improved pharmacokinetic properties may lead to promising therapies and possible clinical application for the treatment of β-thalassemia.

Phase Ib/II Pomdefil clinical trial conducted by the Spanish MM group

This phase I/II trial evaluated the combination of the kinesin spindle protein inhibitor filanesib with pomalidomide and dexamethasone in relapsed or refractory multiple myeloma (RRMM) patients. Forty-seven RRMM patients with a median of three prior lines (2-8) and 94% refractory to lenalidomide were included: 14 in phase I and 33 in phase II. The recommended dose was 1·25 mg/m² of filanesib on days 1, 2, 15, 16, with pomalidomide 4 mg on days 1-21 and dexamethasone 40 mg weekly. The defined threshold for success was achieved, with 18 out of 31 patients obtaining at least minor response (MR) in the phase II. In the global population, 51% of patients achieved at least partial response (PR) and 60% ≥MR, resulting in a median progression-free survival (mPFS) of seven months and overall survival (OS) of 19 months. The main toxicity was haematological. Importantly, patients with low serum levels of alpha 1-acid glycoprotein (AAG) at baseline (<800 mg/l) had a superior response (overall response rate of 62% vs. 17%; P = 0·04), which also translated into a longer mPFS (9 vs. 2 months; P = 0·014). In summary, filanesib with pomalidomide and dexamethasone is active in RRMM although with significant haematological toxicity. Most importantly, high levels of AAG can identify patients unlikely to respond to this strategy. Trial registration: clinicaltrials.gov identifier: NCT02384083.

A Cell-Based Target Engagement Assay for the Identification of Cereblon E3 Ubiquitin Ligase Ligands and Their Application in HDAC6 Degraders

Proteolysis-targeting chimeras (PROTACs) is a paradigm shift for small-molecule drug discovery. However, limited E3 ubiquitin ligase ligands with cellular activity are available. In vitro binding assays involve the expression and purification of a large amount of proteins and they often yield ligands that are inactive in cell-based assays due to poor cell permeability, stability, and other reasons. Herein, we report the development of a practical and efficient cell-based target engagement assay to evaluate the binding affinity of a small library of cereblon ligands to its E3 ligase in cells. Selected cell-permeable E3 ligase ligands derived from this assay are then used to construct HDAC6 degraders with cellular protein degradation activity. Because the assay does not involve any genetic engineering, it is relatively easy to transfer from one cell type to a different one.

[Ultra high-risk refractory multiple myeloma with a complex karyotype including t(14;19)]

A 78-year-old man was hospitalized because of rapid progression of chronic renal failure and diagnosed with multiple myeloma (MM) IgG-λ type ISS-III R-ISS-II with complex karyotype including t(14;19). Even after receiving bortezomib-based regimens, his renal failure progressed. He became dependent on dialysis, which was required three times a week. After introducing the daratumumab (DARA)-based regimen, his renal function improved, the frequency of dialysis decreased to twice a week, and the free light chain (FLC) ratio also improved. However, his myeloma eventually followed a refractory course; therefore, pomalidomide (POM)-dexamethasone (Pd) regimen was administered. Pd regimen had a marked effect and normalized the FLC ratio after three courses of the treatment. However, his myeloma reprogressed with multiple extramedullary masses and he became del(17p) positive; eventually, he died on the 470th day of disease. MM with t(14;19) is rare and has a poor prognosis with a highly aggressive course; however, early introduction of DARA or POM may provide long-term response.

Pomalidomide-associated progressive multifocal leukoencephalopathy in multiple myeloma: cortical susceptibility-weighted imaging hypointense findings prior to clinical deterioration

Although there are several case reports of progressive multifocal leukoencephalopathy (PML) in multiple myeloma (MM), there are few reports of cases associated with pomalidomide. Here, we report the case of a 69-year-old female who had received 41 cycles of pomalidomide and dexamethasone treatment for relapsed/refractory IgG-κ MM presented with right-hand weakness; she was diagnosed as pomalidomide-associated PML. Fluid-attenuated inversion recovery (FLAIR) on admission showed high signals in the bilateral front-parietal lobe white matter, with multiple punctate lesions in the vicinity of the main lesions. These punctate pattern findings on FLAIR were similar to that of natalizumab-associated PML. Susceptibility weighted imaging (SWI) showed hypointense rims within the cortex at unaffected sites, in the initial stages. Subsequently, the clinical manifestations deteriorated, and the FLAIR images showed new hyperintense white matter lesions at the sites where cortical SWI hypointense rims were detected on the initial MRI examination. Our patient's serial MRI findings suggest that cortical SWI hypointense rims appear prior to the visible demyelinating white matter lesions in patients with PML.

Regression of a spinal schwannoma after Pomalidomide

A 77-year old female with a history of neurofibromatosis type 2 (NF2) was diagnosed with a spinal schwannoma that was managed conservatively over a decade. During this time, follow up imaging revealed this lesion had been growing and the patient had become symptomatic from it necessitating surgical decompression. However, the patient had been diagnosed with multiple myeloma and underwent treatment with Pomalidomide chemotherapy which delayed surgery for the spinal schwannoma. Further imaging of the spine revealed significant regression in the size of the spinal schwannoma. This phenomenon has not previously been reported and this report aims to explore the implications of Pomalidomide in patients with NF2 related spinal schwannomas.

[Pomalidomide/cyclophosphamide/dexamethasone combination therapy for relapsed/refractory multiple myeloma accompanied by extramedullary lesions]

We retrospectively evaluated the efficacy of pomalidomide/cyclophosphamide/dexamethasone (PCd) treatment in seven patients with extramedullary disease (EMD). Three of the seven patients achieved VGPR (very good partial response) with PCd therapy. We handled a patient complicated with secondary plasma cell leukemia, which was completely cured with PCd regimen and succeeded to autologous stem cell transplantation. In addition, there were no severe infections during the treatment period. This is the first report demonstrating the efficiency and tolerability of PCd treatment for EMD.

Pomalidomide-Responsive Extramedullary Myeloma Relapsed after Allogeneic Hematopoietic Transplant and Refractory to Multiple Lines of Chemotherapy

Patients who experience extramedullary relapses (EMR) of multiple myeloma (MM) have an adverse prognosis, also in this era of novel agents like proteasome inhibitors and immunomodulatory drugs. We describe the case of an MM patient with EMR at 2 different sites after allogeneic stem cell transplantation. EMR was refractory to bortezomib, anthracycline, and bendamustine, but the patient achieved long-term complete remission (4 years) with pomalidomide and dexamethasone. This supports the hypothesis that this could be due to the graft-versus-myeloma effect during therapy enhanced by pomalidomide.

Successful hematopoietic stem-cell mobilization with plerixafor plus granulocyte-colony stimulating factor in multiple myeloma patients treated with pomalidomide

Autologous stem-cell transplantation is an effective procedure for the treatment of multiple myeloma, and involves the collection of hematopoietic stem cells (HSCs). However, in some patients, HSCs in the bone marrow fail to mobilize. Pomalidomide upregulates CXCR4 in hematopoietic stem cells, in a manner similar to that of lenalidomide, and is, thus, likely to have a negative impact on hematopoietic stem-cell mobilization in multiple myeloma patients. Here, we report the two cases in which hematopoietic stem cells were mobilized using plerixafor plus granulocyte-colony stimulating factor after exposure to lenalidomide and pomalidomide. Use of plerixafor with a sufficient washout period may lead to successful mobilization following pomalidomide use, although further study of this potential use is needed.

Inhibition of Airway Contraction and Inflammation by Pomalidomide in a Male Wistar Rat Model of Ovalbumin-induced Asthma

Asthma is a chronic inflammatory disease of the airways of the lungs. Pomalidomide (POM) a therapy for multiple myeloma has been stated to have an anti-inflammatory effect. The main goal of the present study was to assess its possible effect on airway contraction and inflammation in a rat model of ovalbumin-induced asthma. Different groups of rats received saline or pomalidomide (0.4, 0.8 mg/kg) or dexamethasone (0.6 mg/kg). The asthma was induced by ovalbumin (OVA). Trachea contraction was assayed by organ bath system. Airway histology was assessed using hematoxylin and eosin method. Serum Tumor necrosis factor alpha (TNF-α) level was analyzed by Enzyme-Linked Immunosorbent Assay and Platelet-derived growth factor (PDGFα) Gene expressions were evaluated by Real-time PCR. Pomalidomide prevented ovalbumin-induced airway contraction and histopathological damage. In addition serum, TNF-α level was significantly (p<0.05) decreased in POM treated animals compared to control (asthmatic animals that received POM vehicle). Results indicate that POM prevented the PDGF expression induced by ovalbumin. In conclusion, we found that pomalidomide ameliorated the symptoms, histopathological changes and inflammatory markers induced by ovalbumin in asthmatic rats and these effects might be related to its anti-inflammatory properties.

Pomalidomide, cyclophosphamide, and dexamethasone for relapsed/refractory multiple myeloma patients in a real-life setting: a single-center retrospective study

Pomalidomide dexamethasone is a standard of care for relapsed multiple myeloma (MM) patients who received at least two prior lines of therapy, including both lenalidomide and proteasome inhibitors (PI). We report here a real-life single-center series of 49 consecutive patients with relapsed and refractory MM treated with the triplet pomalidomide cyclophosphamide dexamethasone (PCD) combination. The median of prior lines of therapy was 3 and all patients were previously exposed to proteasome inhibitors and lenalidomide. The overall response rate was 76%, including 27% very good partial response or better. With a median follow-up of 16 months, the median progression-free survival (PFS) was 7.3 months and the median overall survival was not reached. Regarding safety, most frequent toxicity was hematologic, including 37% grade 3-4 cytopenias. Nine patients (18%) discontinued therapy due to adverse event. Our study confirms that PCD combination is feasible and results in favorable response rate and PFS in comparison with pomalidomide dexamethasone alone.

Disseminated adenovirus infection in a patient with relapsed refractory multiple myeloma undergoing autologous stem cell transplantation and pomalidomide/dexamethasone as salvage regimens

BACKGROUND

Disseminated adenovirus (ADV) infection is a fatal complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), however, it is rare following autologous peripheral blood stem cell transplantation (auto-PBSCT) or chemotherapy alone.

CASE

A 66-year-old Japanese female with relapsed and refractory multiple myeloma (RRMM) received auto-PBSCT, achieving partial response. To obtain a greater response, pomalidomide/dexamethasone was started on day 28 after auto-PBSCT, but was stopped on day 41 due to thrombocytopenia, fever, and gross hematuria. Additionally, she complained of abdominal pain on day 46. Blood tests revealed elevation of transaminases and alkaline phosphatase. There was no evidence of bacterial or fungal infections or progression of MM. ADV titer in urine and serum were 3.41 × 10⁵ copies/mL and 6.76 × 10³ copies/mL, respectively. CT scans revealed cystitis, urethritis, and peritonitis. Since more than two organs were infected with ADV, she was diagnosed with disseminated ADV disease. After 5 weeks of supportive care, all symptoms resolved. ADV titer decreased to 5.90 × 10² copies/mL in urine and became negative in serum on day 80. However, she succumbed to the MM a little more than a month later.

CONCLUSION

Disseminated ADV infection can occur even in non-allogeneic transplant settings, such as in severely immunocompromised patients with MM who receive auto-PBSCT and repeated salvage therapies. Although it is a rare event, the mortality rate of this disease is very high, and hence, early diagnosis and interventions are needed in suspected cases.

[Successful management of drug-induced skin rash in a relapsed multiple myeloma patient with pomalidomide desensitization]

A 71-year-old man diagnosed with IgG-κ type multiple myeloma 11 years ago was treated with low doses of pomalidomide (POM, 1 mg/daily) and dexamethasone (20 mg/week) as the third-line of salvage regimen. The treatment was terminated 4 days later owing to the appearance of a severe skin rash, which had also occurred after previous treatment with lenalidomide. After 2 months, POM was readministered via an outpatient desensitization protocol under prednisolone administration. During five cycles of POM-treatment, no severe skin rash appeared, and partial remission was obtained even though the final POM dose was as low as 1 mg/day.

Chemically induced degradation of CK2 by proteolysis targeting chimeras based on a ubiquitin-proteasome pathway

As a ubiquitous, highly pleiotropic and constitutively active serine/threonine protein kinase, casein kinase 2 (CK2) is closely associated with tumorigenesis by its overexpression in cancer cells. Here we report several proteolysis targeting chimeras (PROTACs) via "click reaction" to connect a CK2 inhibitor (CX-4945) and pomalidomide for degradation of CK2 protein. Among them, compound 2 degraded CK2 in a dose and time-dependent manner, and kept CK2 at a low basal level by recruiting ubiquitin-proteasome system. The degradation of CK2 resulted in the reduced phosphorylation of Akt and the up-regulation of p53. As a CK2 protein degrader, 2 showed the analogous cytotoxicity to CX-4945 but with a quite different mechanism of action from the CK2 inhibitor, hinting that degradation of CK2 proteins by PROTACs is a potential way for cancer treatments.

[Recurrent amylase-producing multiple myeloma responding to pomalidomide and carfilzomib-containing therapies]

A 73-year-old woman diagnosed with symptomatic multiple myeloma (MM; IgG-κ type, D&S: IIIA, ISS: 2) was administered bortezomib plus dexamethasone (BD) therapy. Post BD therapy, although autologous hematopoietic stem cell transplantation and thalidomide, lenalidomide, and melphalan/prednisolone/thalidomide (MPT) therapies were also performed, the patient remained unresponsive. However, the disease relapsed, and she eventually developed pantalgia. Therefore, the patient was admitted to our hospital and was administered pomalidomide and dexamethasone (Pd) therapy. The serum amylase (AMY) and urine AMY levels were 6,329 and 6,098 IU/l, respectively, which were salivary gland-type amylase (S-AMY). Notably, the markedly high levels immediately decreased after the first course of the Pd therapy; additionally, the pantalgia also disappeared. The S-AMY level in the supernatant from cultured bone marrow mononuclear cells was higher than that observed in a normal control. In addition, AMY was high when MM previously relapsed, suggesting the presence of AMY-producing MM. Although AMY-producing MM was first reported by Hata et al. in 1988, few cases have been reported in the new-drug era. In conclusion, AMY-producing MM frequently, including in our case (as the patient was refractory to treatment), is difficult to treat. However, our patient positively responded to the novel next-generation drugs such as pomalidomide and carfilzomib.

Salvage therapy post pomalidomide-based regimen in relapsed/refractory myeloma

The combination of pomalidomide and low-dose dexamethasone (Pom-Dex) has proved effective and safe in patients with end-stage relapsed/refractory multiple myeloma (RRMM), otherwise characterized by a very poor outcome. MM remains an incurable disease with unavoidable relapses, and the outcome after pomalidomide is still dismal. However, some patients demonstrate prolonged survival even beyond pomalidomide therapy.We sought to analyze the treatment of RRMM patients following Pom-Dex therapy and the response and survival after this next treatment line.We studied 134 patients treated with Pom-Dex until progression across two IFM studies. Seventy percent of these patients received further therapy after Pom-Dex. Among the treated patients, one third responded and one third maintained stable disease. The median OS for treated patients was 12 months (6.5;17), with 22 and 12.5% of patients surviving beyond 2 and 3 years, respectively. The factors associated with a better outcome were exposure to a triplet-based regimen containing a novel agent, response to therapy, absence of adverse cytogenetic, and a longer time from diagnosis to post pomalidomide therapy.This study suggests that patients relapsing after Pom-Dex therapy can still benefit from a further line of treatment. A subset of these treated patients even displayed a prolonged OS, while the prognosis remained very poor without treatment. An active approach could therefore be recommended even in this adverse situation, however guided by the patients' prognosis factors.

[Transfusion independence achieved with pomalidomide therapy in a patient with primary myelofibrosis]

Primary myelofibrosis (PMF) is commonly associated with anemia. IMiD^® immunomodulatory drugs including thalidomide and lenalidomide have been shown to be effective in improving anemia associated with PMF. However, because of adverse events, their use has been restricted. Herein we report the case of a 67-year-old male patient with transfusion-dependent PMF treated with the immunomodulatory drug pomalidomide in a clinical trial. Significant improvements in anemia and thrombocytopenia were observed with pomalidomide, and the patient recovered from transfusion dependence for 8 months. Although phase 3 trial failed to show the superiority of pomalidomide over placebo, pomalidomide may have some benefit in selected patients with transfusion-dependent PMF.

Pomalidomide

Pomalidomide (originally CC-4047 or 3-amino-thalidomide) is a derivative of thalidomide that is antiangiogenic and also acts as immunomodulatory. Pomalidomide, the recent immunomodulatory agent (IMiD), has shown substantial in vitro antiproliferative and proapoptotic effects. In vivo studies have suggested limited cross-resistance between lenalidomide and pomalidomide. Moreover, pomalidomide achieved very convincing responses in relapsed and refractory multiple myeloma (RRMM) patients, including those, who are refractory to both lenalidomide and bortezomib. Since pomalidomide plus low-dose dexamethasone has shown better responses, progression-free survival (PFS) and overall survival (OS) than high-dose dexamethasone or pomalidomide alone, subsequent trials have pursued or are still investigating pomalidomide triplet combinations, using cyclophosphamide or other novel agents, such as proteasome inhibitors (PI: bortezomib, carfilzomib) or antibodies, like elotuzumab or daratumumab. Pomalidomide has also been assessed in AL amyloidosis, MPNs (myelofibrosis [MF]), Waldenstrom's macroglobulinemia, solid tumors (sarcoma, lung cancer), or HIV, and-for AL amyloidosis and MF-has already been proven to be remarkably active. Due to its potency, pomalidomide was approved for RRMM by the US Food and Drug Administration (FDA) and by the European Medicines Agency (EMA) in 2013 and for drug combination with low-dose dexamethasone in 2015. In June 2017, the FDA further expanded approval for pomalidomide in combination with daratumumab and low-dose dexamethasone for patients with RRMM.

[Achievement of a stringent complete response with low-dose pomalidomide monotherapy in a multiple myeloma patient]

An 80-year-old man presented to our hospital with a thoracic vertebrae compression fracture. He was diagnosed with IgG-λ myeloma (International Staging System stage II, Durie-Salmon stage IIIA). Since melphalan-prednisolone (MP) was not effective, we treated him with lenalidomide and low-dose dexamethasone (DEX) (Ld), achieving a partial response. As DEX provoked edema and psychiatric symptoms, the patient disagreed with its use, and pomalidomide (POM) monotherapy was initiated. Although the POM dosage was reduced to 1-2 mg/day due to somnolence, which was reported as an adverse event, stringent complete response (sCR) was achieved and sustained for 10 months following 11 cycles of low-dose POM monotherapy. It is assumed that sCR was achieved with low-dose POM monotherapy due to its early introduction as well as there being no high-risk chromosomal abnormalities. Even though adverse events develop with a standard dose, a continuation of low-dose POM is considered more important than discontinuation.