Phase 1/2 study of carfilzomib, pomalidomide, and dexamethasone with and without daratumumab in relapsed multiple myeloma

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.

A phase I study of selinexor combined with weekly carfilzomib and dexamethasone in relapsed/refractory multiple myeloma

We performed a phase I study of weekly selinexor, carfilzomib, and dexamethasone (wSKd) in patients with relapsed/refractory multiple myeloma (MM). The primary objective was to identify the maximum tolerated dose (MTD) of wSKd. Secondary endpoints included overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). Prior exposure/refractoriness to carfilzomib was permitted. Thirty patients were enrolled; 26 (87%) had triple-class exposed disease and 6 (20%) received chimeric antigen receptor (CAR) T-cell therapy. Dose level 2 (carfilzomib 70 mg/m² Intravenous [IV] on Days 1, 8, and 15; selinexor 100 mg PO on Days 1, 8, 15, 22; dexamethasone 40 mg on Days 1, 8, 15, 22 of 28-day cycles) was chosen as the MTD, with no DLTs having occurred. The most common hematologic adverse events (AE) were thrombocytopenia (83%), anemia (70%), lymphopenia (50%), and neutropenia (50%). The most common nonhematologic AE were fatigue (70%), nausea (70%), diarrhea (53%), and anorexia (47%). The ORR was 21/30 (70%) overall and 18/23 (78%) at the MTD. At a median follow-up of 12.3 months, the median PFS was 5.3 months and median OS 23.3 months. Responses were similar in carfilzomib naïve and exposed patients. Long-term efficacy of wSKd is modest; wSKd could be employed as a bridging strategy to immunotherapies.

Elotuzumab and Weekly Carfilzomib, Lenalidomide, and Dexamethasone in Patients With Newly Diagnosed Multiple Myeloma Without Transplant Intent: A Phase 2 Measurable Residual Disease-Adapted Study

Importance

Treatment of newly diagnosed multiple myeloma (NDMM) with a quadruplet regimen consisting of a monoclonal antibody, proteasome inhibitor, immunomodulatory imide, and corticosteroid has been associated with improved progression-free survival (PFS) compared with triplet regimens. The optimal quadruplet combination, and whether this obviates the need for frontline autologous stem cell transplant (ASCT), remains unknown. We evaluated elotuzumab and weekly carfilzomib, lenalidomide, and dexamethasone (Elo-KRd) without ASCT in NDMM.

Objective

To investigate the efficacy of Elo-KRd using a measurable residual disease (MRD)-adapted design in NDMM regardless of ASCT eligibility.

Design, Setting, and Participants

This multicenter, single-arm, phase 2 study enrolled patients between July 2017 and February 2021. Median follow-up was 29 months.

Interventions

Twelve to 24 cycles of Elo-KRd; consecutive MRD-negative results at 10-6 by next-generation sequencing (NGS) after cycles 8 (C8) and 12 determined the duration of Elo-KRd. This was followed by Elo-Rd (no carfilzomib) maintenance therapy until disease progression.

Main Outcomes and Measures

The primary end point was the rate of stringent complete response (sCR) and/or MRD-negativity (10-5) after C8 Elo-KRd. Secondary end points included safety, rate of response, MRD status, PFS, and overall survival (OS). As an exploratory analysis, MRD was assessed using liquid chromatography mass spectrometry (MS) on peripheral blood samples.

Results

Forty-six patients were enrolled (median age 62 years, 11 [24%] aged >70 years). Overall, 32 (70%) were White, 6 (13%) were Black, 3 (6%) were more than 1 race, and 5 (11%) were of unknown race. Thirty-three (72%) were men and 13 (28%) were women. High-risk cytogenetic abnormalities were present in 22 (48%) patients. The rate of sCR and/or MRD-negativity after C8 was 26 of 45 (58%), meeting the predefined statistical threshold for efficacy. Responses deepened over time, with the MRD-negativity (10-5) rate increasing to 70% and MS-negativity rate increasing to 65%; concordance between MRD by NGS and MS increased over time. The most common (>10%) grade 3 or 4 adverse events were lung and nonpulmonary infections (13% and 11%, respectively). There was 1 grade 5 myocardial infarction. The estimated 3-year PFS was 72% overall and 92% for patients with MRD-negativity (10-5) at C8.

Conclusions and Relevance

An MRD-adapted design using elotuzumab and weekly KRd without ASCT showed a high rate of sCR and/or MRD-negativity and durable responses. This approach provides support for further evaluation of MRD-guided deescalation of therapy to decrease treatment exposure while sustaining deep responses.

Trial Registration

ClinicalTrials.gov Identifier: NCT02969837.

Interim analysis of a phase 2 minimal residual disease (MRD)-adaptive trial of elotuzumab, carfilzomib, lenalidomide, and dexamethasone (Elo-KRd) for newly diagnosed multiple myeloma (MM)

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Background: The addition of a monoclonal antibody to triplet induction regimens in patients (pts) with MM with intent for autologous stem cell transplant (ASCT) has resulted in higher overall and deep response rates. In this study we are investigating the impact of the addition of Elo to KRd on complete response (CR) and/or MRD-negative rates in newly diagnosed MM regardless of transplant eligibility. Methods: Pts were enrolled from four MM Research Consortium sites into this phase 2 study. All patients receive 12 cycles of Elo-KRd in 28-day cycles: Elo per standard dosing, K 20/56/70 mg/m2 days 1, 8 and 15, R 25 mg days 1-21, and dexamethasone 40 mg days 1, 8, 15, 22. ASCT eligible candidates can undergo stem cell collection after cycle 4 and then resume treatment; pts who elect to proceed to ASCT are censored for response at that time. Pts MRD(-) (<10-5) by NGS after cycles 8 (C8) and 12 (C12) proceed to Elo-Rd until progression. Patients who convert from MRD(+) to MRD(-) between C8 and C12 receive an additional 6 cycles of Elo-KRd (total 18 cycles) followed by Elo-Rd, and pts MRD(+) after C12 receive an additional 12 cycles of Elo-KRd (total 24) followed by Elo-Rd. The primary endpoint of the study is sCR and/or MRD(-) rate after C8 E-KRd. MRD status was determined by ClonoSEQ next generation sequencing (NGS, <10-5) [Adaptive Biotechnologies]. An improvement in the sCR and/or MRD(-) rate by NGS from a historical 30% to 50% at the end of C8 will be considered promising. Results: 44 pts are enrolled, 39 of whom are evaluable for response (cutoff Jan 10 2021). Median age is 62 years (range 43-81, 23% age >70) and 23 (52%) have high-risk cytogenetic abnormalities (HRCA) including 13 (30%) with >2 high-risk abnormalities (6 pts unknown cytogenetics). 34/39 (87%) have MRD trackable by clonoSEQ. The rate of sCR and/or MRD(-) by NGS at the end of C8 is 19/33 (58%), meeting the statistical threshold for establishing efficacy (2 pts censored for elective ASCT before C8 and 4 pts receiving therapy but have not reached C8). With a median follow-up of 24 months, estimated 2-year progression free survival is 87% (100% for standard risk, 79% for HRCA) and estimated 2-year overall survival is 89% (82% for HRCA). No pt who was MRD(-) by NGS after C8 has progressed, including 6 pts with HRCA. Serious adverse events occurred in 30 pts (68%). 89% experienced treatment emergent AEs, the most common (>10%) of which was pneumonia (14%). One pt had grade 5 myocardial infarction. Conclusions: Elo-KRd demonstrates tolerability consistent with known toxicities of these agents and met the primary endpoint of sCR and/or MRD(-) of >50% after 8 cycles. With longer follow-up, the study results may validate that an MRD-adaptive design for de-escalation of therapy in MM can generate deep responses while reducing treatment exposure. Clinical trial information: NCT02969837.

Recommendations and outcomes from a geriatric assessment guided multidisciplinary clinic prior to autologous stem cell transplant in older patients

BACKGROUND

Autologous hematopoietic stem cell transplant (autoHCT) is a mainstay of treatment for multiple myeloma and non-Hodgkin lymphoma but is underutilized in older adults. We investigated the association of vulnerabilities identified by a geriatric assessment (GA)-guided multidisciplinary clinic (MDC) on the receipt of autoHCT and evaluated its ability to predict outcomes in older autoHCT candidates.

METHODS

Patients 50+ years received GA-informed optimization recommendations: 'decline' if unlikely to realize benefits of autoHCT, 'defer' if optimization necessary before autoHCT, and 'proceed' if autoHCT could proceed without delay. We compared characteristics and outcomes of autoHCT recipients (n = 62) to non-autoHCT patients (n = 29) and evaluated GA deficits on outcomes.

RESULTS

91 patients were evaluated; the MDC recommendation was 'decline' for 5 (6%), 'defer' for 25 (27%), and 'proceed' for 61 (67%). AutoHCT recipients had fewer GA-rated impairments relative to non-autoHCT patients, as did patients with a 'proceed' recommendation relative to 'defer'. Among autoHCT recipients, 1-year and 3-year non-relapse morality (NRM) was 0% and 5%, and there was no difference in length of hospitalization, readmission rate, or mortality after transplant by MDC recommendation. Frail grip strength and poor performance status were associated with inferior post-autoHCT progression-free survival and overall survival.

CONCLUSIONS

Patients pursuing autoHCT after MDC-directed optimization achieved excellent outcomes, including patients deferred but ultimately receiving autoHCT. GA-identified functional deficits, especially frail grip strength, may improve risk stratification in older autoHCT candidates. Employing a GA earlier in the disease trajectory to inform early referral to an MDC may increase autoHCT safety and utilization in older patients.

Racial differences in treatment and outcomes in multiple myeloma: a multiple myeloma research foundation analysis

Findings on racial differences in survival in multiple myeloma (MM) have been inconclusive. We assessed differences in outcomes between White and Black individuals among 639 newly diagnosed MM patients in the MM Research Foundation CoMMpass registry with baseline cytogenetic data. Survival curves were constructed using the Kaplan-Meier method. Hazard ratios and 95% confidence intervals were derived from Cox proportional hazard regression models. Age, gender, and stage were similar between Whites (n = 526) and Blacks (n = 113). Blacks had inferior overall survival (OS) compared with Whites and were less likely to receive triplet therapies or frontline autologous stem cell transplant (ASCT). The following factors were significantly associated with inferior OS in multivariate analysis: higher international staging system (ISS) score, ≥1 or ≥2 high-risk cytogenetic abnormalities (HRCA), high-risk gene expression profile (GEP), and lack of ASCT. Multivariate analysis in the Black subset found that only lack of ASCT was significantly associated with inferior OS. The receipt of both triplet induction and ASCT only partly abrogated the effect of race on survival. HRCA did not track with survival in Blacks, emphasizing the need for race-specific risk prognostication schema to guide optimal MM therapy.

Abstract A39: Concordance of 5-hydroxymethylcytosine-modified genes from circulating cell-free DNA and positron emission tomography in multiple myeloma

Background: Positron emission tomography (PET) is one of the current standard-of-care imaging techniques for evaluating extramedullary disease in multiple myeloma (MM); hypermetabolic focal lesions at diagnosis are associated with poor prognosis. Molecular analysis of circulating cell-free DNA (cfDNA) has potential to not only be a noninvasive test for measuring extramedullary disease to complement imaging, but also provide pathobiologic insights. We previously discovered that signatures of the epigenetic modification 5-hydroxyethylcytosine (5hmC) in cfDNA differ between MM and its precursor conditions and predict relapse risk for MM patients at the time of diagnosis. We evaluated differentially modified 5hmC genes between PET-negative and PET-positive patients at the time of MM diagnosis and assessed concordance of the cfDNA 5hmC profiles with PET.

Methods: We prospectively enrolled patients with newly diagnosed MM at The University of Chicago Medical Center from 2010 to 2017. Patients enrolled in the study who underwent standard-of-care PET imaging within 30 days of a corresponding blood draw were evaluated. Blood samples were collected and processed immediately to separate plasma. We profiled 5hmC with DNA extracted from ~2 mL of plasma to construct the 5hmC-seal libraries using the nano-hmC-Seal technology, which then underwent next-generation sequencing. 5hmC sequencing data were mapped to the human genome and annotated to ~22,000 gene bodies. We compared genome-wide 5hmC loci between PET-positive and PET-negative patients with MM. We developed an eight gene-based weighted prognostic score (wp-score) for predicting overall survival by applying the elastic net regularization on Cox proportional hazards model. Next, we evaluated concordance between PET results and wp-score.

Results: A total of 71 MM patients (age, 61.2±10.65 year; males n=42) had at least one PET scan performed and had cfDNA sequencing data available; 29 (36%) patients had an initial PET positive for MM and the remaining 52 had a negative PET. We found 14 differentially modified 5hmC genes between PET-positive and PET-negative patients at baseline (p&lt;0.005). PET positivity at baseline is associated with poor prognosis for MM. We also found that 9 out of 19 (47%) patients with a positive PET had a high wp-score (i.e., worse survival), while 11 out of 32 patients (34%) with a negative PET had a low-risk wp-score.

Conclusions: Differential enrichment of 5hmC-modifications on gene body regions identified from 5hmC profiling of plasma cfDNA at the time of MM diagnosis differentiates patterns of PET imaging and adds complementary prognostic information to PET. These novel findings support the investigation of 5hmC in cfDNA as part of a multimodal approach to enhance prognostication in MM and potentially guide initial therapy.

Citation Format: Benjamin Derman, Zhou Zhang, Jason Karpus, Chang Zeng, Elizabeth Stepniak, Diana West-Szymanski, Rudy Chiu, John Spinelli, Chuan He, Jagoda Jasielec, Andrzej Jakubowiak, Wei Zhang, Brian Chiu. Concordance of 5-hydroxymethylcytosine-modified genes from circulating cell-free DNA and positron emission tomography in multiple myeloma [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr A39.

Measurable residual disease (MRD) assessed by mass spectrometry (MS) in peripheral blood versus next generation sequencing (NGS) in bone marrow in multiple myeloma treated on phase II trial of KRd+ASCT

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Background: MRD-negativity in multiple myeloma (MM) assessed by NGS in bone marrow (BM) aspirate is associated with longer progression free survival (PFS) and overall survival. MS can detect monoclonal protein at a heightened sensitivity in peripheral blood (PB). We sought to assess the concordance of MS in PB and NGS in BM, comparing outcomes by MRD status. Methods: MRD was tested on paired PB and BM samples from transplant (ASCT)-eligible pts with newly diagnosed secretory MM who received treatment on a phase II clinical trial (NCT01816971) with KRd for 4 cycles, ASCT, KRd for 14 cycles, and lenalidomide maintenance (LM). Both NGS and MS were evaluable in 36 pts after a total of 18 cycles of KRd (C18) and in 24 pts after 1 year of LM. MS signatures were identified in pretreatment PB samples. C18 and after 1 year of LM PB samples were evaluated using both MALDI-TOF and liquid-chromatography-MS (LCMS) by the Binding Site Group. Paired MRD by NGS was performed by ClonoSEQ. 20/60 samples reached the limit of detection for 10−6 and 40/60 for 10−5. Results: There was substantial concordance between NGS and MALDI-TOF among the 60 samples ( κ= 0.667, 83% agreement) and fair concordance between NGS and LCMS ( κ= 0.348, 63% agreement). However, all 22 discordant samples (8 with NGS depth 10−6, 14 with NGS depth 10−5) were NGS−/LCMS+. 4/16 (25%) of these pts converted to NGS+, and 3/16 (19%) clinically progressed. There was stronger concordance between LCMS and NGS 10−6( κ= 0.615) than with NGS 10−5( κ= 0.375). At a median follow-up of 56 months, C18 LCMS−(n = 9) was associated with superior PFS vs all LCMS+(n = 27; p = 0.03) and independently vs NGS—/LCMS+ (n = 14; p = 0.04). There were 10 events (including 4 deaths) in the C18 LCMS+ group vs 0 in the LCMS− group. Conclusions: MRD assessment by LCMS in PB appears to reach and possibly exceed the sensitivity of MRD by NGS in BM at a depth of 10−5-10−6. LCMS positivity predicted conversion from NGS— to NGS+ in 25% of discordant cases, and LCMS negativity was a better predictor of superior PFS than MRD negativity by NGS. These observations need confirmation in larger prospective studies.

Impact of an oncology clinical pharmacist specialist in an outpatient multiple myeloma clinic

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Background: Improvements in cancer treatment, supportive care, and the approval of oral chemotherapy medications over the past decade have resulted in an increasing number of cancer patients treated in outpatient settings. Transitioning cancer treatments to the outpatient setting places greater emphasis on proper medication counseling and optimal side effect management. Current literature demonstrates improvements in medication adherence and effective cancer related symptom management with the addition of an oncology pharmacist. Historically, the University of Chicago Medical Center (UCMC) has not employed pharmacists into their ambulatory oncology clinics. UCMC is evaluating pharmacist’s roles in these clinics. Methods: The primary objective of this project is to evaluate the clinical and financial impacts of an oncology clinical pharmacist specialist in an interdisciplinary multiple myeloma (MM) clinic. This will be evaluated by monitoring the interventions made by the pharmacist in clinic through a validated scoring tool. This tool associates a value for each type of intervention made based on current literature and internal evaluations at UCMC. The oncology clinical pharmacist specialist will be available for consult by the MM clinic staff. The pharmacist may be consulted for any medication related inquiry. Based on the consult the pharmacist will categorize their interventions into twelve predefined intervention categories. Results: Study results showed the implementation of a clinical pharmacist specialist into the MM clinic over 39 clinic days resulted in 241 patient consults and 474 interventions made by the pharmacist. The most frequent interventions made by the pharmacist were medication teaching (97), dose adjustments by pharmacist (82) and medication reconciliation (63). Based on the dollar values associated with each intervention type, the value of interventions made by the pharmacist during the study period was $189,441 with a predicted annual value of $757,764. Conclusions: An clinical pharmacist specialist in the MM clinic lead to dramatic and sustainable financial and clinical impacts. Further investigation into other oncology clinics is warranted.

Synergistic Myeloma Cell Death via Novel Intracellular Activation of Caspase-10-Dependent Apoptosis by Carfilzomib and Selinexor

Exportin1 (XPO1; also known as chromosome maintenance region 1, or CRM1) controls nucleo-cytoplasmic transport of most tumor suppressors and is overexpressed in many cancers, including multiple myeloma, functionally impairing tumor suppressive function via target mislocalization. Selective inhibitor of nuclear export (SINE) compounds block XPO1-mediated nuclear escape by disrupting cargo protein binding, leading to retention of tumor suppressors, induction of cancer cell death, and sensitization to other drugs. Combined treatment with the clinical stage SINE compound selinexor and the irreversible proteasome inhibitor (PI) carfilzomib induced synergistic cell death of myeloma cell lines and primary plasma cells derived from relapsing/refractory myeloma patients and completely impaired the growth of myeloma cell line-derived tumors in mice. Investigating the details of SINE/PI-induced cell death revealed (i) reduced Bcl-2 expression and cleavage and inactivation of Akt, two prosurvival regulators of apoptosis and autophagy; (ii) intracellular membrane-associated aggregation of active caspases, which depended on caspase-10 protease activity; and (iii) novel association of caspase-10 and autophagy-associated proteins p62 and LC3 II, which may prime activation of the caspase cascade. Overall, our findings provide novel mechanistic rationale behind the potent cell death induced by combining selinexor with carfilzomib and support their use in the treatment of relapsed/refractory myeloma and potentially other cancers.

Treatment outcome with the combination of carfilzomib, lenalidomide, and low-dose dexamethasone (CRd) for newly diagnosed multiple myeloma (NDMM) after extended follow-up

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Background: We previously reported results from a phase 1/2 trial of CRd in NDMM (NCT01029054), demonstrating a high rate (42%) of stringent complete response (sCR) and overall favorable efficacy /safety after a median of 12 cycles of treatment (tx) and a median follow-up of 13 mo (Jakubowiak et al Blood, 2012). Here we report updated results after extended tx and additional 12 mo of follow-up. Methods: Patients (pts) received 28-day (d) cycles of carfilzomib (CFZ) 20–36 mg/m2 IV (d1, 2, 8, 9, 15, 16), lenalidomide (LEN) 25 mg PO (d1–21), and dexamethasone 40/20 mg PO wkly (cycles 1–4/5–8). For cycles 8–24, CRd was given with a modified CFZ schedule (d1, 2, 15, 16) and then LEN alone after cycle 24. Stem cell transplant was an option after cycle 4. Response was assessed by IMWG plus nCR. Results: As of Nov 2012, 53 pts had received a median of 22 CRd cycles (range 2–24); 7 pts opted for transplant; 24 continued LEN maintenance for median 8 mo (range 1–10). Median follow-up was 25 mo (range 5–37). With extended tx, the CR rate was 64%; sCR improved from 42% to 53%, ≥nCR from 62% to 72%, and ≥VGPR from 81% to 87% (follow-up 13 vs 25 mo); ≥PR remained at 98%. Immunophenotypic CR (IMWG) was achieved in 22/26 evaluated pts. Of pts in sCR, 25% had high-risk cytogenetics per IMWG. In pts who did not proceed to transplant (n=46), the sCR was 59%, CR 70%, ≥nCR 78%, ≥VGPR 91%, and ≥PR 100%. Over the course of tx, depth of response improved. Median time to ≥VGPR was 4 cycles (range 2–17), ≥nCR 4.5 cycles (range 2–15), and sCR 10 cycles (range 4–30); 2 pts converted to sCR during LEN maintenance. At 2 years, the estimated PFS rate was 94% and OS was 98%; for pts with sCR, rates were 96% and 100%, respectively. Adverse event types, rates, and dose modifications during extended tx were comparable with those previously reported. There was 1 death off study due to disease progression. Conclusions: Extended follow-up showed that depth of response continued to improve over the course of prolonged CRd tx, resulting in exceptional CR, sCR, and PFS. Extended tx continued to be well tolerated. The results compare favorably with historical studies in both transplant and non-transplant NDMM. Clinical trial information: NCT01029054.

Initiation of aspirin therapy modulates angiogenic protein levels in women with breast cancer receiving tamoxifen therapy

Aspirin has a range of antineoplastic properties linked to inhibition of cyclooxygenase enzymes in tumor cells, platelet inhibition and to inhibition of angiogenesis. We undertook a prospective study to determine the influence of a 45-day course of aspirin therapy on circulating and intraplatelet levels of selected proangiogenic (vascular endothelial growth factor [VEGF]) and antiangiogenic (thrombospondin-1 [TSP-1]) proteins, and platelet protein release in women diagnosed with breast cancer who were receiving tamoxifen therapy. Initiation of aspirin therapy increases serum and intraplatelet levels of TSP-1 without a corresponding increase in VEGF levels. Following aspirin therapy, VEGF levels decreased (relative to pretreatment levels) while TSP-1 returned to pretreatment levels. Plasma TSP-1 and VEGF levels did not change on aspirin therapy. Aspirin use also decreased thrombin receptor mediated release of TSP-1 and VEGF from platelets. The selective impact on platelet angiogenic protein content and release supports one mechanism by which aspirin can modify the angiogenic balance in women receiving tamoxifen therapy. Aspirin therapy appears to favor an overall antiangiogenic balance in women with breast cancer who are receiving tamoxifen therapy.