The role of Vertebral Augmentation Procedures in the management of vertebral compression fractures secondary to multiple myeloma.

Multiple myeloma (MM) is a systemic disorder characterised by proliferation of B-lymphocytes and plasma cells in the bone marrow. The primary aims of the management of spinal lesions in MM are pain control and fracture stabilisation. Vertebral augmentation procedures (VAP) can be subdivided into percutaneous vertebroplasty (VP) and balloon kyphoplasty (BKP). BKP involves the placement of orthopaedic balloons into the fractured vertebral body, creating a void into which polymethylmethacrylate bone cement is injected. This review outlines the management of spinal lesions in patients with MM, with a focus on the comparative risks and efficacy of vertebroplasty (VP) and balloon kyphoplasty (BKP). Soft tissue masses in MM are highly radiosensitive. Bisphosphonates and newer oncological therapies have decreased the indications for palliative radiotherapy, while spinal bracing can be utilised in selected cases to provide stability. BKP and VP provide equivalent long term pain control after MM vertebral compression fractures (VCF). BKP is superior to non-operative management and VP for restoration of vertebral body height and prevention of segmental kyphosis. Current evidence suggests a greater degree of correction of kyphotic deformity and restoration of mid vertebral height (MVH) with BKP when compared with VP. The literature supports the use of BKP even in the presence of posterior vertebral body wall (PVBW) fractures, a group previously considered a contraindication to VAP. Superior functional outcomes have been reported in patients undergoing early versus delayed BKP (<6-8 weeks). Current evidence supports a lower risk of cement extrusion with BKP than with VP, but serious complications following VAP are rare. MM spinal pathology should be managed in a multidisciplinary setting. Surgical decompression and instrumentation are rarely indicated, due to the radio-sensitivity of soft tissue lesions in MM. BKP is a safe and effective procedure for VCF secondary to MM.

RNA-seq of newly diagnosed patients in the PADIMAC study leads to a bortezomib/lenalidomide decision signature.

Improving outcomes in multiple myeloma will involve not only development of new therapies but also better use of existing treatments. We performed RNA sequencing on samples from newly diagnosed patients enrolled in the phase 2 PADIMAC (Bortezomib, Adriamycin, and Dexamethasone Therapy for Previously Untreated Patients with Multiple Myeloma: Impact of Minimal Residual Disease in Patients with Deferred ASCT) study. Using synthetic annealing and the large margin nearest neighbor algorithm, we developed and trained a 7-gene signature to predict treatment outcome. We tested the signature in independent cohorts treated with bortezomib- and lenalidomide-based therapies. The signature was capable of distinguishing which patients would respond better to which regimen. In the CoMMpass data set, patients who were treated correctly according to the signature had a better progression-free survival (median, 20.1 months vs not reached; hazard ratio [HR], 0.40; confidence interval [CI], 0.23-0.72; P = .0012) and overall survival (median, 30.7 months vs not reached; HR, 0.41; CI, 0.21-0.80; P = .0049) than those who were not. Indeed, the outcome for these correctly treated patients was noninferior to that for those treated with combined bortezomib, lenalidomide, and dexamethasone, arguably the standard of care in the United States but not widely available elsewhere. The small size of the signature will facilitate clinical translation, thus enabling more targeted drug regimens to be delivered in myeloma.

GCS-100, a novel galectin-3 antagonist, modulates MCL-1, NOXA, and cell cycle to induce myeloma cell death.

GCS-100 is a galectin-3 antagonist with an acceptable human safety profile that has been demonstrated to have an antimyeloma effect in the context of bortezomib resistance. In the present study, the mechanisms of action of GCS-100 are elucidated in myeloma cell lines and primary tumor cells. GCS-100 induced inhibition of proliferation, accumulation of cells in sub-G(1) and G(1) phases, and apoptosis with activation of both caspase-8 and -9 pathways. Dose- and time-dependent decreases in MCL-1 and BCL-X(L) levels also occurred, accompanied by a rapid induction of NOXA protein, whereas BCL-2, BAX, BAK, BIM, BAD, BID, and PUMA remained unchanged. The cell-cycle inhibitor p21(Cip1) was up-regulated by GCS-100, whereas the procycling proteins CYCLIN E2, CYCLIN D2, and CDK6 were all reduced. Reduction in signal transduction was associated with lower levels of activated IkappaBalpha, IkappaB kinase, and AKT as well as lack of IkappaBalpha and AKT activation after appropriate cytokine stimulation (insulin-like growth factor-1, tumor necrosis factor-alpha). Primary myeloma cells showed a direct reduction in proliferation and viability. These data demonstrate that the novel therapeutic molecule, GCS-100, is a potent modifier of myeloma cell biology targeting apoptosis, cell cycle, and intracellular signaling and has potential for myeloma therapy.

Pooled analysis of safety data from clinical trials evaluating acalabrutinib monotherapy in mature B-cell malignancies.

Bruton tyrosine kinase (BTK) inhibition is an effective therapy for many B-cell malignancies. Acalabrutinib is a next-generation, potent, highly selective, covalent BTK inhibitor. To characterize acalabrutinib tolerability, we pooled safety data from 1040 patients with mature B-cell malignancies treated with acalabrutinib monotherapy in nine clinical studies (treatment-naïve: n = 366 [35%], relapsed/refractory: n = 674 [65%]; median [range] age: 67 [32-90] years; median [range] prior treatments: 1 [0-13]; median [range] duration of exposure: 24.6 [0.0-58.5] months). The most common adverse events (AEs) were headache (38%), diarrhea (37%), upper respiratory tract infection (22%), contusion (22%), nausea (22%), fatigue (21%), and cough (21%). Serious AEs (SAEs) occurred in 39% of patients; pneumonia (6%) was the only SAE that occurred in ≥2%. Deaths due to AEs occurred in 52 patients (5%); pneumonia (n = 8) was the only fatal AE to occur in ≥3 patients. AEs led to treatment discontinuation in 9%. Rates for the AEs of interest (all grades) included infections (67%), hemorrhages (46%), neutropenia (16%), anemia (14%), second primary malignancies (12%), thrombocytopenia (9%), hypertension (8%), and atrial fibrillation (4%). This pooled analysis confirmed acalabrutinib's tolerability and identified no newly emerging late toxicities, supporting acalabrutinib as a long-term treatment for patients with mature B-cell malignancies.

Alternate day pomalidomide retains anti-myeloma effect with reduced adverse events and evidence of in vivo immunomodulation.

We previously reported that daily dose pomalidomide (CC-4047), a thalidomide analogue, has excellent anti-myeloma activity but is associated with myelosuppression and deep vein thrombosis. We report here a phase 1 study to determine the maximum tolerated dose (MTD) of pomalidomide at 1 mg, 2 mg, 5 mg and 10 mg on alternate days (ad). Twenty patients with relapsed myeloma were treated. Grade 4 neutropenia occurred in all patients receiving 10 mg and the MTD was defined as 5 mg ad. No thrombotic events were observed. Pomalidomide was continued following the 4-week MTD study in 17/20 patients for a median of 14 months. 10% of patients had a complete response and >50% reduction in paraprotein was achieved in 50% of subjects. Progression-free survival was 10.5 months and median overall survival was 33 months. A significant rise was observed in the proportion of CD8(+) cells. Alternate day pomalidomide was associated with a marked reduction in the incidence of thrombosis whilst maintaining excellent anti-myeloma activity. This trial provides further in vivo evidence that pomalidomide modulates the immune system in myeloma patients. Phase 2 studies to further assess the optimal schedule of administration and anti-myeloma activity of this agent are planned.