Citations

Abstract Background: Current dogma for the management of patients with PV dictates controlling erythrocytosis (to goal hematocrit levels of <45% (males) or <42%(females)) to decrease risks of thrombohemorrhagic complications. Control is achieved by either phlebotomy (through induction of iatrogenic iron deficiency), and/or direct myelosuppression (through hydroxyurea, interferon-alpha, or anagrelide). Although phlebotomy is clinically considered a very benign therapy, we hypothesize that PV associated fatigue is exacerbated by iron deficiency induced fatigue (Qual Life Res2000;9:5(491–7)), and evaluated the impact of therapeutic control of erythrocytosis on PV patients. Methods: A detailed analysis of patients with PV whom responded to an international web based survey of MPD patients which registered responses regarding diagnosis, disease course, current medications, current blood counts, frequency of phlebotomy, constitutional symptoms, and fatigue (FACT-An and Brief Fatigue Inventory). Results: A total of 405 self reported PV patients (median age 56; 48% female) from a wide geographic international distribution responded. Individuals were a median of 4 years from their initial diagnosis of PV (range 0–36). Prior PV associated complications were reported as thrombotic (n=98; 24%), hemorrhagic (n=101; 25%), or both events (n=37; 9%). When these latter values were combined with age (i.e. >60 years) 61% of patients (n=246) would be considered high risk. Therapy for their PV was reported by 96% (n=388) patients, with 89% (361) having been phlebotomized, 72% (n = 291) received aspirin, 64% (n = 261) having received 1 or more myelosuppressive agent (hydroxyurea 53% (n = 216), anagrelide 22% (n = 88), interferon-alpha 16% (n = 63)). Amongst patients whom were phlebotomized over the past year (43%; n =174: median 4 units (range 1–18)), 53% (n = 92) received concurrent myelosuppressive therapy. Amongst patients whom originally, but no longer required phlebotomy 35% (n = 142), 94% (n = 134) were receiving myelosuppressive treatments. QOL assessments indicated fatigue as measured by both instruments is clearly increased across the PV respondents compared to published controls for those instruments (p<0.001). Additionally, although the burden of fatigue was not significantly higher in “high-risk” PV, fatigue levels were higher amongst those with prior thrombo-hemorrhagic events (p=0.03, or both types of events p<0.01). In regards to the impact of PV therapy upon fatigue, the burden of this symptom was not significantly diminished for those individuals on phlebotomy alone compared to those on cytoreductive therapy. Neither did fatigue levels correlate with the frequency or intensity of phlebotomy. Additionally, although fatigue burden was high (compared to controls) amongst patients on cytoreductive therapy, no agent had a clear advantage in alleviating (or disadvantage in exacerbating) fatigue. Conclusions: Fatigue amongst patients with PV is significantly increased compared to controls, and no therapeutic option seems to have a significant advantage with regards to fatigue. Given the multifactorial and subjective nature of fatigue it is impossible to separate the individual contributions of disease activity and therapy to the burden of fatigue in these patients. Hopefully, targeted therapy against the molecular origins of myeloproliferation in these patients will lead to better improvements in fatigue than current options offer.

Abstract Background: Debate continues as to the clinical relevance of subclassifying patients with the myeloproliferative disorder (MPD) MMM into the subgroups of agnogenic myeloid metaplasia (AMM), post-polycythemic myeloid metaplasia (PPMM), and post-thrombocythemic myeloid metaplasia (PTMM). We looked to validate previously described phenotypic variability amongst subtypes, and explore relevant and differences in constitutional symptoms. Methods: An detailed analysis of patients with MMM whom responded to an international web based survey of MPD patients which registered responses regarding diagnosis, disease course, complete blood counts, co-morbidities (Charlson Co-morbidity index), symptoms, and fatigue (Fact-An and Brief Fatigue Inventory (BFI)). Results: A total of 456 patients self described as MMM responded of which 32.3% had AMM (n = 148), 38.0% % had PPMM (n = 174), and 29.7% had PTMM (n = 136). Detailed breakdown of differences in demographics, clinical course, current laboratory studies, treatment history, and current symptoms are outlined in the table below. Phenotypic Variability Amongst 458 MMM Patients Category AMM (N=148; 32.3%) PPMM (N=174; 38.0%) PTMM (N=136; 29.7%) MMM Total (N=458) Δ between groups (p = ) Hb = Hemoglobin; SCT = Stem Cell Transplant Age (Median) 61 57 57 58 0.09 Sex (% Males) 60% 49% 30% 47% <0.01 Yrs from MPD Dx 5 6 8 6 <0.01 Labs/ Prior History Hb (g/dL) 11.0 13.7 11.6 12.1 <0.01 % with RBC Tx 43% 6% 11% 20% <0.01 Leukocytes (×10(9)/L) 8.0 7.6 7.2 7.7 0.64 Platelets (×10(9))/L) 200 352 396 321 <0.01 % with Splenomegaly 76% 49% 41% 54% <0.01 % with Prior Thrombosis 10% 22% 31% 21% <0.01 % with Prior Bleed 16% 20% 31% 22% 0.01 Treatment History for the MMM % with Prior Tx for MPD 64% 88% 77% 77% <0.01 % Medical Therapy 57% 70% 75% 67% <0.01 # Meds (Median (Range)) 1 (0–8) 2 (0–6) 2 (0–6) 2 (0–8) <0.01 % with Splenectomy 8% 5% 6% 6% 0.48 % with SCT 6% 1% 1% 3% <0.01 MMM Associated Constitutional Symptoms % with Fatigue 85% 81% 85% 84% 0.56 % with Bone Pain 51% 46% 44% 47% 0.51 % with Fevers 19% 17% 18% 18% 0.87 % with Pruritus 39% 69% 39% 50% <0.01 % with Night Sweats 55% 58% 53% 56% 0.67 % with Weight Loss 30% 15% 16% 20% <0.01 Overall the data suggests patients with AMM are more likely male, with greater burdens of anemia, splenomegaly, and weight loss. However they are less likely to have experienced thrombohemorrhagic complications and have received fewer MPD medications. In contrast PPMM patients (not unsurprisingly) have little trouble from anemia, but have the most pruritus. Patients with PTMM are most likely female, with the highest platelet counts, and the greatest likelihood of thrombohemorrhagic complications. Additionally, all three subgroups of MMM had significant fatigue compared to published controls for both fatigue instruments (P<0.0001) yet there was no difference between MMM subtypes for the severity of fatigue. Conclusions: A large unselected series of MMM patients supports that although constitutional symptoms are significant and similar amongst MMM subgroups, these patients have variable burdens of other MPD manifestations.

Abstract Background: Scant data exists regarding the burden of fatigue and constitutional symptoms in patients with myeloproliferative disorders (MPDs) (essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis with myeloid metaplasia (MMM)). Methods: An Internet based survey of MPD patients regarding clinical course, blood counts, constitutional symptoms, and fatigue (FACT-AN and Brief Fatigue Inventory (BFI)). Results: Patient Demographics: A total of 1179 MPD patients (median age 56; 41.4% male) internationally (76% USA: 50 states, 30 countries, 6 continents) responded to the survey. Self reported diagnoses were PV (35%), ET (26%), or MMM (39%). Clinical History: 1025 patients (87%) had undergone MPD therapy (drugs 70.5%, phlebotomy 44.1%, other 16%). Thrombosis (n=261, 22%), hemorrhage (N=272; 23%), and splenomegaly (N=478 (43%) were frequently reported. Blood tests (available in 917) showed 39% were anemic, 7% transfusion dependent. Symptoms: Fatigue, pruritus, night sweats and bone pain were present across the majority of MPD patients (see table). Additionally it was observed that these symptoms appeared with nearly equal frequency in PV as in MMM patients. However MMM patients displayed more advanced features (fevers, night sweats and weight loss). MPD Associated Constitutional Symptoms in 1179 Patients SYMPTOM PV (N=405) ET (N=304) MMM (N=456) MISSING (N=14) TOTAL (N=1179) P VALUE Fatigue 344 (84.9%) 220 (72.4%) 381 (83.6%) 7 945 (81.1%) <0.0001 Pruritus 265 (65.4%) 120 (39.5%) 228 (50.0%) 3 613 (52.6%) <0.0001 Night Sweats 199 (49.1%) 123 (40.5%) 254 (55.7%) 4 576 (49.4%) 0.0002 Bone Pain 174 (43.0%) 125 (41.1%) 214 (46.9%) 4 513 (44%) 0.2480 Fevers 53 (13.1%) 26 (8.6%) 81 (17.8%) 2 160 (13.7%) 0.0013 Weight Loss 39 (9.6%) 22 (7.2%) 93 (20.4%) 0 154 (13.2%) <0.0001 Spleen Pain 17 (4.2%) 27 (8.9%) 30 (6.6%) 4 74 (6.3%) <0.0001 Fatigue (82% MPD linked) was significantly increased across all MPD subtypes compared to published controls for both the BFI (P<0.0001) and Fact-An (P<0.0001). Additionally 69% curtail social activity because of fatigue, 35% need assistance with activities of daily living, and 11% reported MPD associated medical disability. Fatigue strongly correlated with multiple MPD disease features including: anemia, bone pain, constitutional symptoms, pruritus, splenic pain, smoking, thrombosis, and hemorrhagic events (all p<0.0001). Interestingly, even in “asymptomatic” MPD patients (those without anemia, splenomegaly, or thrombohemorrhagic complications) (n=279)) 24% (41% PV, 31% ET, 28% MMM) described significant fatigue worse than published controls. Conclusions: Fatigue and other constitutional symptoms are a significant burden to MPD patients, despite current therapies employed. Additionally fatigue is also a significant problem even in MPD patients lacking other advanced disease features. Clearly, direct attempts to improve fatigue (through pharmacologic and non-pharmacologic interventions) are necessary.

Abstract Background: Little objective data exists regarding the impact that myeloproliferative disorders (MPDs) (essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis with myeloid metaplasia (MMM)) have on quality of life. Methods: An Internet based survey of MPD patients regarding clinical course, co-morbidities (through the Charlson Co-Morbidity Index), fatigue (through two validated fatigue instruments (FACT-AN and Brief Fatigue Inventory (BFI)), and exercise tolerance (Godin Leisure-Time Questionnaire). Results: Patient Demographics: A total of 830 MPD patients (median age 56; 60.8% male) from a broad geographic distribution (77% USA: 50 states, 30 countries, 5 continents) responded to the survey. Self reported diagnoses were PV (N=272; 33%), ET (N=221; 27%), or MMM (N=329; 40%) for a median of 5 years (range (0–53). Clinical History: 708 patients (87%) had undergone treatment for their MPD (drugs 84.6%, phlebotomy 49.5%, other 16%). A history of thrombotic (n=195, 24%) or hemorrhagic events (N=214; 26%) were frequently reported. Blood tests (available in 597 a median 1.65 months prior to survey) showed 37% were anemic (7% transfusion dependent). Additionally, 347 (44%) had splenomegaly, painful in 21%. Symptoms: Frequent symptoms reported included fatigue (90%), pruritus (57%), night sweats (54%), bone pain (48%), undesired weight loss (15%), and/or fevers (15%). 41% felt restricted in their activities, and 89 (11%) were medically disabled secondary directly to their MPD. 82% of patients felt their fatigue was linked to their MPD. Additionally 69% curtail social activity because of fatigue, and 41% need some degree of assistance with activities of daily living. Charlson co-morbidity index demonstrated 722 (87%) had minimal co-morbidities strengthening the association between fatigue and their MPD. The burden of fatigue decreased from MMM to PV to ET respectively (p=0.0002). Results from both fatigue assessment tools (FACT-AN and BFI) were highly correlated. Fatigue (FACT-AN fatigue subscale) strongly correlated with multiple MPD disease features including: anemia, bone pain, constitutional symptoms, pruritus, splenic pain, hemorrhagic events (all p<0.0001) and thrombosis(p=0.01). Additionally, currently smoking (as opposed to being a prior smoker) was highly associated with increased fatigue (p<0.0001). Interestingly, even in “asymptomatic” patients (those without anemia, splenomegaly, or thrombohemorrhagic complications (n=187)) 73% (n=128; 40% PV, 32% ET, 27% MMM; p=N.S.) described moderate to severe MPD associated fatigue. Reported physical activity was diminished (Godin Leisure Score) between MPD patients and published norms, with 38% describing minimal to no exercise. Overall, 86% stated fatigue was the major obstacle to exercise. Conclusions: Fatigue is an extremely common problem in patients with MPDs despite current therapies, and a minimal burden of co-morbidities in the majority of patients. Fatigue is also common in patients lacking advanced MPD disease features, or thrombohemorrhagic complications. Clearly, direct attempts to improve fatigue (through pharmacologic and non-pharmacologic interventions) are necessary.

Abstract Background: Myelofibrosis (MF) shortens survival but also compromises quality of life from disease associated splenomegaly and constitutional symptoms (fatigue, weight loss, night sweats, and bone pain). No current validated instrument of patient reported outcomes (PRO) captures the spectrum of MF associated symptoms. In an era of rapid development and testing of therapeutic agents which may impact the natural history and symptoms associated with MF (such as JAK2 inhibitors) a uniform and validated instrument for capturing the presence, severity (and potentially improvement) of MF symptoms is needed. We sought to develop and validate such an instrument, the myelofibrosis symptom assessment form (MFSAF). Methods: Based upon the results in our MF QOL survey (Cancer2007;109(1):68–76), we developed the MFSAF to assess fatigue (via the brief fatigue inventory (BFI-Cancer1999;85:1186)), additional symptoms were independently assessed for presence and severity on a scale from 0 (absent) to 10 (worst possible) for splenomegaly associated symptoms (early satiety, pain, inactivity, cough) night sweats, itching, bone pain, fever, unintentional weight loss as well as an estimate of overall quality of life. Additionally, patients provided feedback on the quality and nature of the MFSAF, and also completed for comparison validated instruments including the Memorial Symptom Assessment Scale (MSAS), the Insomnia Severity Index (ISI), and the Brief Pain Index. Physician input was included including their assessment of patient’s fatigue, spleen symptoms, and quality of life (blinded to patient’s responses) as well as clinical history, lab and exam findings. Results: MFSAF Results 34 MPD patients were enrolled (24 MF, 10 in the comparison group (4 polycythemia vera (PV), 6 essential thrombocythemia (ET)). the MFSAF was rated by patients as easy to understand (median score 1, range 0–6), and “addressed most of my symptoms” (median score 1, range 0–6) both on a scale of 0 (as good as possible to 10 as bad as possible). When asked if a symptom was not addressed (open ended response) no single symptom was named more than once. As we have previously reported fatigue was common with BFI scores (median 3.6 (0–10) for MF and 2.5 (range 0.2–3.8) for the ET/PV group (increasing BFI score associated with worsening fatigue) worse than median score of published “healthy” controls 2.2. Additional MF associated symptoms were captured well by the MFSAF with splenic, constitutional symptoms, and QOL (median 3 (range 0–7) MF, median 2 (0–3) ET/PV) documented easily and worse than ET/PV controls. Physicians estimation of QOL was excellent (median 3 (0–8) for MF, median 2 (0–4) for ET/PV). MFSAF Comparison to other Instruments: The MSAS demonstrated more adverse values for MF (than ET/PV) in the PSYCH (psychologic stress; mean-1.27 (STD DEV 0.80), PHYS (physical symptoms; mean 0.90 (STD DEV 0.53)), GDI (Global Distress Index mean-1.29 (STD DEV 0.77)) and a total MSAS symptom score (mean 0.85 (std dev (0.49)) comparable with advanced renal disease (PSYCH 0.99, PHYS 0.99, GDI 1.27, and MSAS of 0.81; J of Pall Med2007;10(6):1266), as well as advanced lung disease, AIDS, and various advanced malignancies. Individual, previously validated MSAS questions were all highly correlated (all p<0.01) with MFSAF (in italic) counterparts including lack of energy (fatigue), cough (same), pain (both abdominal pain and bone pain), sweats (night sweats), itching (same), and weight loss (same). Further validation of pain measurements in the MFSAF came from comparison to the BPI where both individually the presence, and intensity of pain (both abdominal and bone) were highly correlated (all p<0.01). Insomnia, not yet included in the MFSAF, was present in 68% and 63% of patients (MSAS and ISI, respectively). Additionally, problems with sexual interest, or activity, was noted in 35% of patients to the MSAS. Conclusions: Currently available instruments of PRO and symptoms are lengthy, and individually incomplete for assessing the presence and severity of the diverse nature of symptoms associated with MF. The proposed MFSAF, was comprehensive and well understood by patients and the results for the individual symptoms assessed were highly correlated with previously validated instruments for other conditions as well as with physicians perceptions of fatigue and QOL. The MFSAF, with the addition of questions regarding insomnia and sexuality, should be utilized in all trials of therapeutic agents in MF patients in which symptomatic improvements are an endpoint.

Abstract Background: The combination of cediranib (ced) and olaparib (olap) improves progression-free survival and overall response rates (ORR) in women with recurrent plat sensitive high-grade serous (HGS) ovarian cancer compared to olap alone. In this Phase 2 study of ced/olap in women with relapsed ovarian cancer (NCT02345265), we observed an ORR of 74% with ced/olap in plat sensitive relapsed patients (pts) and an ORR of 20% in plat resistant pts. BROCA-HR was performed to characterize tumor HRD status and to correlate this with the activity of ced/olap in the plat sensitive and resistant settings. Methods: Pts with relapsed ovarian cancer across 11 centers were enrolled to 2 cohorts, either plat sensitive or resistant. All pts received ced 30mg daily and olap tablets 200mg BID. Archival, pre-treatment, and on-treatment biopsies were collected on all pts where safely feasible; pts also had the option of undergoing a post-progression biopsy. A baseline blood sample was collected for germline testing and matched control. Available samples were sequenced with BROCA-HR, and HRD status was determined by (1) presence of an HR-related mutation or (2) an increase in loss of heterozygosity (LOH) score. Results: 72 pts were enrolled, with 70 pts receiving study treatment (35 plat sensitive and 35 plat resistant). BROCA-HR analysis is complete on 60 samples, with 10 samples in final analysis. The concordance of HRD status by presence of an HR-related mutation or by LOH score was relatively low (agreement=36/60=60%, Cohen's Kappa=0.28). In 19 pts with a germline BRCA mutation, 16 were HRD+ by LOH (LOH high), 2 were HRD- by LOH (LOH low), and 1 not quantifiable. 3 pts had a somatic BRCA mutation; 1 was LOH high, 1 LOH low, and 1 not quantifiable. 4 pts had non-BRCA somatic HR-related mutations (3 CDK12; 1 ATR); 3 were LOH high and 1 LOH low. Of the 34 pts without HR-related mutations, 15 were LOH high, 16 were LOH low, and 3 not quantifiable. In 29 plat sensitive pts with BROCA-HR results, 18 were HRD+ by mutation (12 germline BRCA, 3 somatic BRCA, 3 somatic other), and 16 were HRD+ by LOH (LOH high). The ORR in plat sensitive pts by HRD status with available HRD results was: 22/29=75.9% (13/18=72% HRDmut+; 9/11=82% HRDmut-); (12/16=75% LOH high; 6/9= 67% LOH low). In 31 plat resistant pts with BROCA-HR results, 8 were HRD+ by mutation (7 germline BRCA, 0 somatic BRCA, 1 somatic other), and 19 were HRD+ by LOH. The ORR in plat resistant pts by HRD status with available HRD results was: 7/31=22.6% (4/8=50% HRDmut+; 3/23=13% HRDmut-, P=0.05); (7/19=37% LOH high; 0/11= 0% LOH low, P=0.03). Updated results with the full data set are pending. Conclusion: Ced/olap has clinical activity in women with relapsed ovarian cancer, both in the plat sensitive and plat resistant settings. In women with plat sensitive disease, where response rates are high, HRD status by presence of an HR-related mutation or LOH status does not appear to provide significant additional information regarding likelihood of response. In women with plat resistant disease, the presence of HRD by an HR-related mutation or LOH status is correlated with a higher likelihood of response. Citation Format: Joyce F Liu, Su-Chun Cheng, Robert M Wenham, Andrea E Wahner Hendrickson, Deborah K Armstrong, Nancy Chan, David E Cohn, Jung-Min Lee, Richard T Penson, Mihaela Cristea, James Abbruzzese, Koji Matsuo, Alexander B Olawaiye, Jennifer Curtis, Geoffrey Shapiro, Ursula A Matulonis, Elise Kohn, Percy Ivy, Elizabeth M Swisher. Correlation of homologous recombination deficiency (HRD) status by BROCA-HR sequencing with response to combination cediranib and olaparib in relapsed ovarian cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A074. doi:10.1158/1535-7163.TARG-19-A074

Abstract Background: Abemaciclib plus nonsteroidal aromatase inhibitors (AI) demonstrated efficacy with a tolerable safety profile as initial treatment for postmenopausal women with HR+, HER2− advanced breast cancer in the MONARCH 3 trial. In the intent-to-treat (ITT) population, the updated progression-free survival (PFS) with 12 months of additional follow-up was 28.2 versus 14.8 months (HR [95% CI]: 0.525 [0.415, 0.665]; p<.0001) in the abemaciclib plus AI versus placebo plus AI arms, respectively. Here we report data from the additional 12 months of follow-up on tumor response for the ITT population and exploratory subgroups previously identified as significantly prognostic (Di Leo et al. 2018). Methods: In MONARCH 3, a randomized, double-blind, phase III trial, 493 postmenopausal women with HR+, HER2− advanced breast cancer and no prior systemic therapy in the advanced setting, received an AI (anastrozole or letrozole) plus abemaciclib or placebo. From the October 31, 2018 cutoff, secondary endpoints including objective response rate ([ORR], complete response [CR] + partial response [PR]), time to response (TTR), and duration of response ([DoR], time from a confirmed CR or PR until disease progression or death) were assessed in the ITT population and exploratory subgroups previously reported as significantly prognostic. Waterfall plots will be used to illustrate the magnitude of change in tumor size for each subgroup (to be presented). Results: In patients with measurable disease, the ORR was 62.5% (95% CI: 56.7, 68.2) in the abemaciclib plus AI arm and 44.7% (95% CI: 36.2, 53.2) in the placebo plus AI arm (p≤.001). Additional follow-up confirmed that all prognostic subgroups received benefit from the addition of abemaciclib to AI, consistent with the ITT population, as evidenced by change in ORR, with the largest effects observed in subgroups of patients with liver metastases, progesterone receptor-negative tumors, high grade tumors, or treatment-free interval of <36 months (Table). Median TTR was similar between the two treatment arms (abemaciclib plus AI: 3.62 months; placebo plus AI: 3.65 months), and this was generally consistent across subgroups. Responses were more durable in the abemaciclib plus AI arm (median DoR: 32.71 months; 95% CI: 25.74, -) versus the placebo plus AI arm (median DoR: 17.49 months; 95% CI: 11.61, 22.19), including in poor prognostic subgroups. Conclusions: Extended follow-up in the MONARCH 3 trial further confirmed that the addition of abemaciclib to AI is associated with durable tumor responses, including those in patients with clinically poor prognostic characteristics. References: Di Leo A et al. NPJ Breast Cancer. 2018;4:41. Clinical trial information: NCT02246621 This study was funded by Eli Lilly and Company Table: Objective Response RateAbemaciclib + AIPlacebo + AIORR ChangeNn (%)Nn (%)%Measurable disease population269168 (62.5)13259 (44.7)17.8Liver metastasesYes4727 (57.45)306 (20.00)37.45No222141 (63.51)10253 (51.96)11.55Progesterone receptor statusNegative6137 (60.66)298 (27.59)33.07Positive206130 (63.11)10351 (49.51)13.60Treatment-free interval<36 months3117 (54.84)225 (22.73)32.11≥36 months7442 (56.76)3216 (50.00)6.76Tumor gradeHigh5739 (68.42)2811 (39.29)29.13Intermediate/ Low13992 (66.19)7535 (46.67)19.52ECOG PS111275 (66.96)5022 (44.00)22.96015793 (59.24)8237 (45.12)14.12Bone-only diseaseNo256162 (63.28)12253 (43.44)19.84YesNA*NA*NA*NA*NA*N= total number of patients in each subgroup; n= number of responder patients; NA=not applicable*Response rate not reported for bone-only disease because majority of lesions were not measurable Citation Format: Joyce O’Shaughnessy, Stephen Johnston, Miguel Martin, Jens Huober, Masakazu Toi, Valerie AnneMarie Andre, Holly Rene Martin, Molly Catherine Hardebeck, Angelo Di Leo, Matthew Philip Goetz. Updated subgroup tumor response of abemaciclib plus aromatase inhibitor for hormone receptor positive (HR+), HER2 negative advanced breast cancer (MONARCH 3) [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-09.

10509 Background: PST allows for improved surgical outcomes and response assessment without compromising long term outcomes. PST is an attractive model for assessing surrogate markers of response to therapy. We hypothesized that changes in tumor standardized uptake values corrected for lean body mass (SUL) max on FDG- PET by cycle 1 day 15 (C1D15) of therapy would predict pathological complete response (pCR) to PST in women with stage 2-3, grade 2-3, HER2-negative breast cancer. Methods: TBCRC008 is a multicenter placebo-controlled trial that investigates pCR following 12 weeks of preoperative carboplatin and albumin-bound paclitaxel with or without vorinostat. FDG-PET followed by tumor biopsies were performed at baseline and C1D15. We correlated % reduction in SULmax on FDG-PET (PERCIST 1.0; Wahl RL, J Nuc Med 2009) with pCR (no invasive cancer in breast/axilla). We compared % reduction in SULmax between responders (pCR) and non responders (no pCR) using nonparametric Wilcoxon rank sum test. We explored association of % reduction in SULmax at pre-specified cutoff with response using Fisher’s exact test and logistic regression. We correlated baseline, C1D15, and % change in Ki67 at C1D15 with pCR. Results: Accrual is complete. Of 62 women enrolled (10/2009-11/2011), 40 have completed study PST and surgery (median age 47.5 [range 30-68], ER-positive 67%). Overall pCR was 26%. In an intent to treat analysis (n=39), we observed a significant difference in median % reduction in SULmax between responders vs not (66.6% vs 32.4%, p <0.001). We observed a higher proportion of reduction in SULmax ≥ 60% in responders vs not (80% vs 3.5%, p <0.001). The differences in baseline, C1D15 and % change in Ki67 were not significant between responders and non-responders. Conclusions: Change in SULmax on FDG-PET 15 days after initiating PST was significantly greater in patients with pCR versus no pCR. Future studies will determine whether altering therapy based on early changes in SULmax will improve pCR. Unblinded data from all participants will be presented at the meeting.

TPS1140^ Background: NKTR-102 is a topoisomerase I inhibitor-polymer conjugate that hydrolyzes to provide continuous exposure to SN-38. A phase 2 trial of single-agent NKTR-102 was conducted in pts with 3rd-line MBC; 2 schedules (q14d; q21d) investigated a dose of 145 mg/m2. ORR was 29% (including 3% CR) with the prior ATC subset demonstrating an ORR of 31%. Dosing q21d was better tolerated; in this arm, median PFS and OS equaled 5.3m and 13.1m, respectively. Trial Design: Pts will be randomized 1:1 to receive single-agent NKTR-102 or TPC in an open-label, randomized, multicenter phase 3 study in pts with advanced breast cancer. Key Entry Criteria: Adult females, with ECOG 0 or 1 with adequate liver, kidney and marrow function. All pts must have received prior therapy with ATC (these drugs can be administered in the neo/adjuvant or locally advanced/metastatic setting). Prior A is not mandated if contraindicated. Prior toxicities must have resolved to ≤ Grade 1 (except sensory neuropathy ≤ Grade 2; complete resolution of prior diarrhea). Pts with brain metastases may be eligible, if lesions are stable for prior 3 weeks without steroids. Methods: Primary efficacy endpoint is OS. Secondary endpoints include: ORR by RECIST v1.1, clinical benefit rate (ORR+SD > 6 months), PFS and QoL. NKTR-102 is given IV at 145 mg/m2 over 90-min every 21 days without premedications. Pts randomized to TPC receive 1 of the following: eribulin, ixabepilone, vinorelbine, gemcitabine, paclitaxel, docetaxel or nab-paclitaxel (the agent must be available at the treating institution). Pts are stratified by region, prior eribulin and receptor status (TNBC, Her2+ or Other). Target Accrual: ~840 pts will be required for sufficient events to occur in the planned follow-up time; OS will be compared using a two-sided log-rank test; 1 interim analysis will occur when 50% of the deaths are reported. PK sampling is performed in a subset of pts. CTCs (isolated by Apocell ApoStream technology) are serially assessed for potential predictive markers of response and toxicity. Enrollment is expected to remain open until late 2013.