Abstract P5-15-01: The use of 18F-FDG PET/CT as an initial staging procedure for stage II-III breast cancer reduces false positives, costs, and time to treatment: A multicenter value analysis in the I-SPY2 trial

Introduction: Diagnostic metastatic staging imaging (SI) for asymptomatic stage I-II patients (pts) is not routinely recommended, but is warranted in stage II-III pts with high risk biological subtypes, where previous trials have shown up to a 15% rate of de novo metastatic disease. NCCN guidelines endorse CT CAP and bone scan (STD) for stage III pts, but not PET/CT, and PET/CT is not covered in most parts of the country. We present data on the performance and value of PET/CT.

Methods: Data were available for 799 high risk clinical stage II-III pts screened for I-SPY2 at UCSF, Uminn, UAB, and Georgetown. Of these, 564 pts ranging in age from 25-81 (median = 48) had complete records that were retrospectively reviewed for SI and potential false positives (FP), defined as incidental findings on SI proven benign by subsequent workup. Economic evaluation was conducted from the payer perspective using the mean national 2018 Medicare Physician Fee Schedule and representative costs from the UCSF billing department. The incremental cost effectiveness ratio (ICER) measured the cost of using PET/CT per percent patient (pt) who avoided a FP.

Results: The rate of de novo metastatic disease was 4.8% (38/799), range 3.6-6.4%. Of the 564 pts with complete records, diagnostic SI varied significantly among the four sites (p < 0.0001). STD was used for most pts at UAB (92.8%, 141/152) and Georgetown (85.7%, 54/63), while PET/CT was used for most pts at UCSF (86.6%, 226/261) and Uminn (63.6%, 56/88). Chest X-ray was used for 29.5% (26/88) at Uminn. There were significantly more pts with FP in the group that received STD (22.1%, 51/231) vs. PET/CT (11.1%, 33/298) (p < 0.05). Mean time between incidental finding on SI to determination of FP was 10.8 days. When controlling for institution, mean time from cancer diagnosis to initiation of neoadjuvant chemotherapy was significantly different between STD (44.3 days) and PET/CT (37.5 days) groups (p < 0.05). When aggregating the four sites using mean costs from the 2018 Medicare Physician Fee Schedule, the mean cost/pt was $1132 for STD vs. $1477 for PET/CT. The mean increase in price from baseline SI costs due to FP workup was $216 (23.6%) for STD vs. $65 (4.6%) for PET/CT. The ICER was $31 per percent pt who avoided a FP. When analyzing UCSF pts alone using representative reimbursements from Medicare, the mean cost/pt was $1236 for STD vs. $1081 for PET/CT; using representative reimbursements from Anthem Blue Cross, the mean cost/pt was $3080 for STD vs. $1662 for PET/CT. The ICERs were -$10 and -$95 per percent pt who avoided a FP, respectively.

Conclusion: As compared to STD metastatic staging workup, PET/CT added value by decreasing FP two-fold. This reduced direct costs of FP workup procedures that took a mean time of 10.8 days to resolve. PET/CT also accelerated treatment start. Reducing the chance of FP workup for metastatic disease is of enormous value to pts. Our data establish the value of PET/CT for staging in our high risk clinical stage II-III trial population and highlight the need for alignment between hospital pricing strategies and payer coverage policies in order to deliver high value care to pts.

Citation Format: Hyland CJ, Varghese F, Yau C, Beckwith H, Khoury K, Varnado W, Hirst G, Chien J, Yee D, Isaacs C, Forero-Torres A, Esserman L, Melisko M, I-SPY2 Consortium. The use of 18F-FDG PET/CT as an initial staging procedure for stage II-III breast cancer reduces false positives, costs, and time to treatment: A multicenter value analysis in the I-SPY2 trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-15-01.

Abstract P2-14-01: The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL

Background: In women with breast cancer receiving neoadjuvant chemotherapy, residual cancer burden (RCB) predicts distant recurrence and survival. In those with high risk tumors, locoregional recurrence (LRR) remains a concern, and has been associated with type of local therapy received. We evaluated the impact of local therapy on LRR in the ISPY-2 TRIAL.

Methods: Data were analyzed in Stata 14.2, using Chi2 test, log rank test, and a Cox proportional hazards model. RCB was considered a categorical variable (0/1 versus 2/3), as described in prior publications. Breast surgery categories were lumpectomy +/- radiotherapy, or mastectomy +/- radiotherapy. Axillary surgery was defined as sentinel lymph node (SLN) surgery (≤6 nodes removed) or axillary dissection (>6 nodes).

Results: Follow up data from the I-SPY2 TRIAL were available for 630 patients (median follow up 2.76 yrs, range 0.4-7.2). Type of local therapy was significantly associated with clinical stage at presentation, with stage III patients most frequently undergoing mastectomy + radiation (p<0.001). Women with higher RCB were more likely to undergo mastectomy than those with lower RCB (61.3% vs 48.8% mastectomy rate, p=0.002), and more likely to receive adjuvant radiotherapy (62.0% vs 53.9%, p=0.048). There was no association between clinical stage, type of surgery, or radiotherapy and LRR (Table). Higher RCB was significantly associated with LRR, with 3 year locoregional recurrence free rate of 95.1% in RCB 0/1 versus 89.9% in RCB 2/3 (p=0.003).

In a Cox model adjusting for clinical stage, tumor subtype, surgical therapy, RCB status, nodal radiation, and age, significant predictors for LRR were tumor subtype and RCB status. Hazard ratio (HR) for LRR in those with RCB 0/1 was 0.39 compared to those with RCB 2/3 (95% CI 0.17-0.87, p=0.021). There was no difference in LRR between breast conservation and mastectomy; within the breast conservation group, those who had lumpectomy alone had higher hazard of LRR compared to those having lumpectomy + radiation (HR 3.1, 95% CI 1.1-9.2, p=0.043).

Conclusions: Extent of surgical therapy was not associated with local tumor control, regardless of advanced tumor stage at presentation. Rather, tumor biology and response to therapy were the best predictors of LRR. These data highlight the opportunity to minimize the morbidity of extensive surgical therapy for patients with excellent response to systemic therapy.

LRR rates by clinical features and treatment status FrequencyLRR RateP valueClinical Stage  0.5I240 (47.5%)5.8% II185 (36.6%)8.7% III80 (15.8%)6.3% Tumor Subtype  0.014ER+PR+Her2-161 (26.4%)3.1% ER+PR-Her2-56 (9.2%)3.6% Her2+176 (28.9%)6.3% Triple negative216 (35.5%)11.1% Local therapy  0.169Lumpectomy85 (13.5%)11.8% Lumpectomy with radiation198 (31.4%)5.6% Mastectomy173 (27.5%)5.2% Mastectomy with radiation174 (27.6%)8.6% Axillary surgery  0.23None5 (0.8%)20% SLN329 (52.2%)5.8% ALND296 (47%)8.5% Axillary radiation  0.535Yes42 (6.7%)9.5% No588 (93.3%)7.0% Axillary management  0.2No surgery or radiation5 (0.8%)20.0% SLN312 (50%)5.3% SLN+Axillary radiation17 (2.7%)8.3% ALND271 (43%)10.3% ALND+Axillary radiation25 (4%)5.4% RCB  0.0020/1293 (50.1%)3.8% 2/3292 (49.9%)10.3% 

Citation Format: Silverstein J, Suleiman L, Yau C, Price ER, Singhrao R, Yee D, DeMichele A, Isaacs C, Albain KS, Chien AJ, Forero-Torres A, Wallace AM, Pusztai L, Ellis ED, Elias AD, Lang JE, Lu J, Han HS, Clark AS, Korde L, Nanda R, Northfelt DW, Khan QJ, Viscusi RK, Euhus DM, Edmiston KK, Chui SY, Kemmer K, Wood WC, Park JW, Liu MC, Olopade O, Leyland-Jones B, Tripathy D, Moulder SL, Rugo HS, Schwab R, Lo S, Helsten T, Beckwith H, I-SPY 2 TRIAL Consortium, Berry DA, Asare SM, Esserman LJ, Boughey JC, Mukhtar RA. The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-14-01.

Abstract P4-22-12: Ribociclib + fulvestrant in postmenopausal women with HR+, HER2– advanced breast cancer (ABC)

Background: Endocrine therapy (ET) is the treatment backbone for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) ABC, but efficacy is limited by ET resistance. The cyclin-dependent kinase (CDK) 4/6–cyclin D (CCND1)–retinoblastoma (Rb) and phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathways have been implicated in ET resistance. CDK4/6 and PI3K/mTOR inhibitors act synergistically with ET in preclinical and clinical studies of HR+ breast cancer. Ribociclib (LEE011; CDK4/6 inhibitor) + fulvestrant ± alpelisib (BYL719) or buparlisib (BKM120) in HR+, HER2– ABC is being investigated in a Phase Ib/II study (NCT02088684). Here, we present results from the ribociclib + fulvestrant combination, with intermittent and continuous ribociclib dosing.

Methods: Postmenopausal patients (pts) with HR+, HER2– ABC refractory to aromatase inhibitors received ribociclib intermittently (600 mg/day, 3-weeks-on/1-week-off; Arm A) or continuously (400 mg/day; Arm B; following Arm A safety evaluation) + fulvestrant (500 mg; Cycle 1 Day 1 and 15; subsequent cycles Day 1). Primary objective: dose-limiting toxicities (DLTs) to confirm the recommended Phase II dose of ribociclib + fulvestrant. Secondary objectives: safety, pharmacokinetics, and preliminary antitumor activity (RECIST v1.1); biomarkers that may correlate with response were also assessed.

Results: As of March 10, 2016, 24 pts received ribociclib + fulvestrant (Arm A, n=13; Arm B, n=11); 4 pts in Arm B were ongoing; median duration of exposure was 7.4 (Arm A) and 4.5 (Arm B) months. Median number of prior regimens: 4 (Arm A) and 3 (Arm B). Treatment discontinuation (n; Arm A, Arm B) was due to disease progression (11, 4), physician decision (1, 2), and adverse events (AEs; 1, 1). DLTs in Cycle 1 (n; Arm A, Arm B) were Grade [G] 3 pulmonary embolism (1, 0) and G3 aspartate aminotransferase elevation (0, 1). The most common G3/4 drug-related AE (Arm A, Arm B) was neutropenia (62%, 36%); 5 pts had QTcF prolongation >60 ms (n; 4, 1).

Common all-Grade drug-related AEs (>35% pts) n (%)Arm A (n=13)Arm B (n=11)Neutropenia10 (77)7 (64)Fatigue9 (69)3 (27)Nausea6 (46)5 (46)Anemia6 (46)0 (0)Reduced appetite5 (39)1 (9)

Best overall responses (BORs; n; Arm A, Arm B): partial response (PR; 3, 1), stable disease (SD; 9, 6), and neither complete response nor progressive disease (NCRNPD; non-measurable disease; 1, 4). Overall response rate: 23% (Arm A) and 9% (Arm B); disease control rate (BOR of complete response, PR, SD, or NCRNPD): 100% in both arms. Next-generation sequencing data (n; Arm A, Arm B) were available for 16 pts (7, 9): 5 pts had CCND1 alterations (PR [1, 0], SD [2, 1], and NCRNPD [0, 1]); 11 pts had PIK3CA alterations (PR [1, 0], SD [3, 4], and NCRNPD [1, 2]); 2 of these pts had both CCND1 and PIK3CA alterations (SD [1, 0] and NCRNPD [0, 1]).

Conclusions: Ribociclib + fulvestrant has a manageable safety profile and shows preliminary clinical activity in pretreated pts with HR+, HER2– ABC. Both ribociclib intermittent and continuous dosing schedules were well tolerated. Clinical responses were observed in tumors with and without CDK4/6–cyclin D–Rb and PI3K/mTOR pathway alterations.

Citation Format: Tolaney SM, Forero-Torres A, Boni V, Bachelot T, Lu Y-S, Maur M, Fasolo A, Motta M, Pan C, Dobson J, Hewes B, Chin Lee S. Ribociclib + fulvestrant in postmenopausal women with HR+, HER2– advanced breast cancer (ABC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-22-12.

Abstract P6-12-04: Phase 1 study of the antibody-drug conjugate (ADC) SGN-LIV1A in patients with heavily pretreated metastatic breast cancer

Background

LIV-1, a transmembrane protein and downstream target of STAT3, is highly expressed in breast cancer cells. It is associated with lymph node involvement and metastatic progression. SGN-LIV1A is an anti-LIV-1 antibody conjugated via a protease-cleavable linker to monomethyl auristatin E (MMAE). Upon binding to cell-surface LIV-1, SGN-LIV1A is internalized and releases MMAE, which binds to tubulin and induces G2/M arrest and apoptosis.

Methods

This is an ongoing, phase 1 dose-escalation study evaluating safety, tolerability, pharmacokinetics, and antitumor activity of SGN-LIV1A (q3 wks IV) in women with LIV-1-positive, unresectable, locally advanced or metastatic breast cancer (LA/MBC) (NCT01969643). Patients (pts) with measurable disease and ≥2 prior cytotoxic regimens for LA/MBC were eligible. Pts with ≥Grade 2 neuropathy were excluded. Response was assessed per RECIST v1.1; pts with stable disease (SD) or better could continue treatment until disease progression or intolerable toxicity. At completion of dose escalation in hormone receptor-positive/HER2-negative (HR+/HER2–) and triple-negative (TN) pts, expansion cohorts were opened to further evaluate safety and antitumor activity of monotherapy in TN pts and combination therapy with trastuzumab (Tz) in HER2-positive (HER2+) pts. Pre- and post-treatment tumor biopsies were done to evaluate LIV-1 expression and other correlative endpoints.

Results

To date, 39 pts (18 HR+/HER2–, 21 TN) have received a median of 3 cycles (range, 1–10) of SGN-LIV1A monotherapy at doses of 0.5–2.8 mg/kg. Median age was 57 yrs (range, 33–79). At baseline, pts had a median of 4 prior cytotoxic regimens for LA/MBC (range, 2–8); 36 had visceral disease and 25 had bone involvement. No dose-limiting toxicities (DLT) occurred in 19 DLT-evaluable pts; maximum tolerated dose was not exceeded at 2.8 mg/kg. Treatment-emergent adverse events (AEs) reported in ≥30% of pts were: fatigue (64%), nausea (54%), alopecia (46%), decreased appetite (41%), constipation (39%), neutropenia (33%), and vomiting (31%). Peripheral neuropathy was reported in 9 pts (23%). Most AEs were Grade 1/2, except neutropenia (all ≥Grade 3). Four pts discontinued treatment due to AEs (acute respiratory distress syndrome, nausea, pneumonia, tachycardia). In dose escalation, modest activity was observed in 17 efficacy evaluable (EE) HR+/HER2- pts, with a disease control rate (DCR) of 59% (10 SD), including 1 pt with SD≥24 wks. Among the 17 EE TN pts (dose escalation plus cohort expansion), the overall response rate (ORR) was 41% (7 PR), DCR was 82% (7 PR, 7 SD) and clinical benefit rate (CBR=OR+SD≥24 wks) was 53% (9 pts). For TN pts, median PFS was 17.1 wks (95% CI: 6.0, 18.4); 6 pts remain on treatment.

Of 281 MBC tumor samples evaluated for LIV-1, 93% were positive; 81% had moderate-to-high expression (H-score ≥100).

Conclusions

LIV-1 is expressed in almost all MBC tumors. SGN-LIV1A monotherapy has been generally well tolerated and shown encouraging antitumor activity in heavily pretreated TN MBC, with a PR rate of 41% and a CBR at ≥24 wks of 53%. Response duration data continue to evolve. Enrollment continues in the TN monotherapy expansion cohort and the HER2+ combination cohort with Tz.

Citation Format: Forero-Torres A, Modi S, Specht J, Miller K, Weise A, Burris III H, Liu M, Krop I, Pusztai L, Kostic A, Li M, Mita M. Phase 1 study of the antibody-drug conjugate (ADC) SGN-LIV1A in patients with heavily pretreated metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-04.

P5-11-07: Receptor Concordance in Triple-Negative Breast Cancer (TNBC) Recurrences

Background: The phenotype of TNBC is defined by absence of estrogen (ER) and progesterone receptors (PR) and lack of amplification of the HER2 oncogene. It is an aggressive form of breast cancer, and despite sensitivity to contemporary chemotherapy, TNBC have a poorer prognosis than ER positive phenotypes, marked by early relapses. This study examines the concordance of receptor status in recurrences among patients with TNBC. Methods: After obtaining IRB approval, we identified patients with triple negative breast cancer treated at the University of Alabama at Birmingham between 1998 and 2010. Patient and tumor characteristics and disease status were recorded. Patients with ER, PR, or HER2 (3+) positivity on immunohistochemistry (IHC), or HER2 amplification by fluorescence in situ hybridization were excluded. Data regarding the receptor status of the recurrence, if known, was documented. Results: Five hundred and two women with TNBC were diagnosed at our institution between 1998 and 2010. Of these patients, 95/502 (19%) had recurrences. Twenty-seven (28%) were local, 18 (19%) were regional, 35 (37%) were distant, and 15 (16%) were both local-regional and distant. These women ranged in age from 33 to 84 years of age. Of the women with a recurrence, 78/95 (82%) had a biopsy confirming breast cancer recurrence. Of those biopsied, 33/78 (42%) had receptor studies performed, and of these, 30 included data for estrogen, progesterone and HER2 receptors. The remaining 3 had only IHC for estrogen receptors performed. Twenty-two/thirty (73%) had concordance on their biopsy with their initial TNBC status, whereas 8/30 (27%) women developed a pathologically discordant recurrence. Conclusion: In this single institution study of TNBC patients, approximately one quarter of patients developed a pathologically discordant distant recurrence noted at biopsy. It is unclear whether patients experiencing a pathologically discordant recurrence differ in prognosis from those with concordant recurrences. Further study is necessary to evaluate this and determine whether routine biopsy based on pathologic discordance rates and outcomes are warranted.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-11-07.

P1-14-01: Randomized Phase II Trial of Weekly vs. q 2-Weekly vs. q 3-Weekly Nanoparticle Albumin-Bound Paclitaxel with Bevacizumab as First-Line Therapy for Metastatic Breast Cancer

Background: Nanoparticle albumin-bound paclitaxel (nab-P) 260 mg/m2 is superior to paclitaxel 175 mg/m2 (P) every 3 weeks (Gradishar et al. JCO 2005) in metastatic breast cancer (MBC), and weekly uninterrupted P is more effective than q3wk P in MBC (Seidman et al. JCO 2008). Bevacizumab (bev) nearly doubles response rate and time to progression (TTP) when added to P as 1st line therapy for MBC (Miller et al. NEJM 2007).

Methods: This open-label, phase II study randomized patients (pts) to nab-P at 260 mg/m2 q3wk (arm A) vs. 260 mg/m2 q 2wk with filgrastim (arm B) vs. 130 mg/m2 weekly uninterrupted (arm C), all with bev (15 mg/kg q 3 weeks arm A, 10 mg/kg q 2 weeks arms B and C). Patients were required to have measurable, HER2 negative MBC and no prior chemotherapy for MBC. The primary endpoints were response rate and toxicity.

Results: Of 212 pts randomized, 208 (75 arm A, 54 arm B, 79 arm C) were treated, with balanced demographics and baseline characteristics. The median age was 57 (range 29–85), 82% were postmenopausal and 89% had visceral disease (64% lung, 50% liver). ECOG PS 0:60%, 1:35%, 2:5%. 62% had prior neo-adjuvant or adjuvant chemotherapy for early stage disease: anthracycline: 54%, taxane: 38%. No significant differences in confirmed complete and partial response rates were noted (A: 40%, B: 44%, C: 46%). Median TTP was longer in Arm C (9.0 months) versus both arms B (6.3 months) and A (8.0 months), overall p=0.065. There were no differences in overall survival (Arm A: 21.3 months, Arm B: 19 months, Arm C: 25.3 months). As per protocol-specified stopping rule, arm B was closed early due to an unacceptable safety profile with significantly more grade ≥ 2 fatigue (B:57%, A: 39%, C:39%, p=0.048) and bone pain (B:19%, A:10%, C:4%, p=0.024). Sensory neuropathy was common; grades 2/3/4: Arm A: 29%/32%/1%, Arm B: 15%/50%/2%, Arm C: 27%/43%/1%). Sensory neuropathy was commonly readily reversible with dose delay and reduction. Febrile neutropenia occurred in <2% of pts in all arms. Arm C patients experienced significantly less arthralgia compared with arms A and B, but dose delays were frequent (86% of pts) on this planned uninterrupted weekly schedule. Bevacizumab-related events were consistent with prior phase III trials of taxane/bev; there were no new safety signals.

Conclusions: Significant and similar antitumor activity was observed in all arms. Weekly nab-P with bev (arm C) resulted in longer TTP. Weekly nab-P with bev (arm C) appears to have the highest therapeutic index, however sensory neuropathy is limiting, suggesting that a 3 week on/1 week off schedule could be preferable and should be studied comparatively.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-14-01.

An update on the dosimetric analysis of concurrent radiation therapy and trastuzumab on early cardiac events

121

Background: The impact of radiation therapy (RT) with concurrent trastuzumab on early cardiac morbidity is relatively unknown. Trastuzumab’s radiosensitizing properties may augment both early and late effects of RT. This retrospective review update provides an analysis of cardiac event (CE) development in patients treated with concurrent RT and trastuzumab with a focus on RT heart dose.

Methods: Sixty-five patients treated with concurrent RT (30 left, 33 right, 2 bilateral) and trastuzumab at the University of Alabama at Birmingham were identified. Patient data for pre-existing heart disease, cardiac risk factors, drug regimen, and CEs were recorded. Dosimetric parameters of maximum heart dose, mean heart dose, heart volume receiving 5, 10, 15, 20 and 30Gy (V5, V10, V15, V20, V30) were also analyzed. Endpoints include the occurrence of CEs at any time in relation to RT and those specifically after the start of RT.

Results: In addition to receiving trastuzumab, 80% of patients received doxorubicin. 15.4% had preexisting heart disease. The mean heart dose for all patients was 248cGy. With a median follow-up of 24.5 months, six patients developed CEs (9.2%), and three of these cases occurred after RT initiation (4, 4, and 0.5 months post-RT). All six CEs occurred during treatment with trastuzumab and consisted of congestive heart failure. Analysis of the heart dose maximum, mean, V5, V10, V15, and V20, V30 were similar in patients with and without CEs, and small differences between groups did not reach statistical significance. CE incidence was significantly associated with smoking (p=0.0037) but not hypertension, diabetes or pre-existing heart disease.

Conclusions: This updated retrospective dosimetric analysis did not find a correlation between concurrent trastuzumab and RT on the development of early cardiac events. Modern era RT with 3D conformal planning, the use of heart blocks, and breath hold techniques will continue to decrease the dose to the heart. Longer follow-up will be needed for analysis of the impact of modern technologic advances and late cardiac morbidity.

Long-term treatment of CTCL with the oral PNP inhibitor, forodesine

8552

Background: Forodesine is a potent inhibitor of purine nucleoside phosphorylase (PNP) that leads to T-cell selective intracellular accumulation of dGTP, resulting in apoptosis. Methods: An open-label dose escalation study of oral forodesine (40–320 mg/m2 daily) for 4 wks with extended therapy was performed to determine the maximum tolerated and/or optimal biologic dose (OBD). Additional subjects were accrued at an OBD (80 mg/m2) to further assess safety and clinical efficacy. Subjects with refractory CTCL, stages IB-IV were eligible. The primary efficacy endpoint (objective response rate [ORR]) was defined as ≥ 50% improvement by a severity-weighted assessment tool (mSWAT). Results: The overall intent to treat response rate was 17 of 64 (27%) subjects or 14 of 36 (39%) at the OBD. As of October 2008, nine of 64 subjects (14%) have received forodesine treatment for >12 months. This cohort of 9 subjects is further examined. Six discontinued treatment (median time on treatment 440 days): 4 for progressive disease, 1 withdrew consent, and 1 due to an adverse event (Diffuse Large B-cell Lymphoma). Three are continuing on therapy for 416, 710, and 863 days. Median age was 68 years (range 42, 81), and all but one was ≥ stage III. They had received a median of 3 prior systemic therapies including 8 of 9 with prior bexarotene. Five of 9 subjects had a response (2 with complete response, 3 with partial response, and 4 with stable disease). Related AEs were experienced by 7 of 9 subjects. The most frequent were nausea (44%), fatigue, peripheral edema, dyspnea, and urinary casts (all 22%). Grade 3 or higher related AEs were experienced by 2 of 9 subjects (Diffuse Large B-Cell Lymphoma as previously mentioned and peripheral edema). There were no hematologic or infection AEs related to forodesine. Grade 3 lymphopenia and CD4 count < 200 were noted in 8 of 9 and 4 of 9 subjects respectively. The risk of any infection AE regardless of cause in these 9 subjects was 15 per 100 person-months of forodesine exposure compared to 59 in all other subjects (n=55). Conclusions: Forodesine has an acceptable safety profile and efficacy in these CTCL subjects treated for 12 months or longer.

[Table: see text]

Complete remissions with weekly dosing of SGN-35, a novel antibody-drug conjugate (ADC) targeting CD30, in a phase I dose-escalation study in patients with relapsed or refractory Hodgkin lymphoma (HL) or systemic anaplastic large cell lymphoma (sALCL)

8500

Background: A defining feature of HL and sALCL is CD30 expression on malignant cells. The ADC SGN-35 comprises an anti-CD30 antibody conjugated to the antitubulin agent monomethyl auristatin E (MMAE). SGN-35 causes cell cycle arrest and apoptosis by binding to CD30 on the tumor cell surface, internalizing, and releasing MMAE into the cell. In a previous phase 1 study with q3 wk dosing, 54% of pts achieved an objective response (CR/PR) at SGN-35 doses ≥1.2 mg/kg [ASH 2008 abstract 1006]. Methods: To assess if more frequent dosing might maximize anti-tumor activity with acceptable tolerability, a multicenter, phase 1, weekly dosing, dose-escalation study (3+3 design) was conducted in pts with refractory or recurrent HL or sALCL. SGN-35 was administered weekly at doses of 0.4–1 mg/kg (2-hr IV infusions). Pts with stable disease or better (Cheson 2007) after two 28-day cycles (6 doses) were eligible to continue SGN-35 treatment. Results: In 17 pts, median age was 38 yrs (range 25–67). Pts received a median of 4 prior therapies; 65% received an autologous SCT. MTD has not been defined. One related G3 event (diarrhea) and no related G4 events occurred. The most common related adverse events were G1/G2 rash, nausea, and peripheral neuropathy. Exposure to SGN-35 (AUC) increased relative to dose level. Multiple CRs were observed at higher doses ( table ); observed time to response in the 1 mg/kg dose group was approximately 8 wks. The 7 pts with CRs all remain on treatment. Enrollment to SGN-35 monotherapy continues at 1.2 mg/kg; combination therapy will be subsequently explored. Conclusions: SGN-35 was generally well tolerated and induced CRs in 7 of 8 evaluable pts at the two highest doses in heavily pretreated patients. Pivotal trials of this antibody-drug conjugate will initiate in early 2009.

[Table: see text]

[Table: see text]

Evaluation of a gene signature to predict single agent dacetuzumab (SGN-40) activity in patients with DLBCL

11063

Background: Dacetuzumab (SGN-40) is a humanized IgG1 monoclonal antibody that binds to CD40, mediates effector cell functions, and activates downstream apoptosis signaling pathways. Dacetuzumab has shown single-agent activity in relapsed/refractory DLBCL in phase I and phase II trials, with multiple objective responses and 1/3 of patients demonstrating tumor shrinkage, defined as a decrease in tumor volume (SPD) of at least 10%. We previously reported a 14-gene signature (ASH 2008 #1593) that was strongly associated with dacetuzumab sensitivity in DLBCL cell lines. Here, we report an initial evaluation of the gene signature as a classifier of patients likely to demonstrate tumor shrinkage after dacetuzumab therapy. Methods: The original 14 microarray probes were chosen for high correlation with in vitro dacetuzumab sensitivity (IC25) in 31 NHL cell line models. Matching qRT-PCR probes were developed and confirmed to correlate with the microarray probes in paired cell line samples. In this retrospective analysis, archived paraffin blocks from a 26 patient subset of the phase I and II trials, with a diagnosis of DLBCL and available tumor measurements, were assayed by qRT-PCR. Results: Overall, 42% of patients (11/26) exhibited decreased SPD of at least 10%. Of those who were marker +, 10 out of 13 (78%) had 10% or better decreases in SPD, whereas only 1 of 13 patients who were marker - demonstrated tumor shrinkage (8%). The overall accuracy for predicting tumor shrinkage was 85% (one-sided P=0.002, by permutation test). Among the 14 genes contributing to the multivariate signature, CD22 and VNN2 were the most strongly down-regulated in specimens from patients without at least a 10% decrease in SPD (P=0.14 and P=0.10, respectively), while IGF1R and CTSC were the most strongly up-regulated (P=0.05 and P=0.08, respectively). Conclusions: A 14-gene signature appears to predict tumor shrinkage in DLBCL patients receiving dacetuzumab in single-agent clinical trials (P=0.002). A larger clinical data set will be analyzed to further evaluate the correlation of this gene signature with objective clinical response rates..

[Table: see text]

Randomized phase II trial of nanoparticle albumin-bound paclitaxel in three dosing schedules with bevacizumab as first-line therapy for HER2-negative metastatic breast cancer (MBC)

1006

Background: Nanoparticle albumin-bound paclitaxel (nab-P) 260 mg/m2 is superior to paclitaxel 175 mg/m2 (P) every 3 weeks (Gradishar et al., J Clin Oncol. 2005). Weekly uninterrupted P is more effective than q3wk P in MBC (Seidman et al., J Clin Oncol. 2008). Bevacizumab (bev) nearly doubles response rate and time to progression (TTP) when added to P as 1st line therapy for MBC (Miller et al., N Engl J Med. 2007). Methods: This open-label, phase II study randomized patients (pts) to nab-P at 260 mg/m2 q3wk (arm A) versus 260 mg/m2 q2wk with filgrastim (arm B) versus 130 mg/m2 weekly uninterrupted, all with bev (15 mg/kg q3wk arm A, 10 mg/kg q2wk arms B and C). Pts were required to have measurable, HER-2-negative MBC and no prior chemotherapy for MBC. The primary endpoints were response rate and toxicity. Results: Accrual is complete, with 25% of pts still on study as of December 1, 2008. Of 208 pts randomized, 202 (72 arm A, 54 arm B, 76 arm C) were treated, with balanced demographics and baseline characteristics. The median age was 56 (range 29–85). 89% had visceral disease and 61% had prior neo-adjuvant or adjuvant chemotherapy. No significant differences in confirmed complete and partial response rates were noted (A: 42%, B: 42%, C: 41%). TTP was longer in arm C (9.2 months) versus both arms B (6.4 months) and A (7.7 months), overall p = 0.028. As per protocol-specified stopping rule, arm B was closed early due to unacceptable safety profile with significantly more grade ≥ 2 fatigue (B:57%, A: 39%, C:39%, p = 0.048) and bone pain (B: 19%, A: 10%, C:4%, p = 0.024). Neurotoxicity grade ≥ 2 was equivalent across all 3 arms (50%); febrile neutropenia occurred in <2% of pts in all arms. Arm C had significantly less arthralgia, myalgia, and nausea compared with arms A and B. Conclusions: Significant antitumor activity was observed in all arms. Weekly nab-P with bev (Arm C) resulted in a significantly longer TTP. Weekly nab-P with bev (Arm C) appears to have the highest therapeutic index, however sensory neuropathy is limiting, suggesting a 3 week on/1 week off schedule could be preferable and should be studied comparatively.

[Table: see text]

A study of pre-operative (neoadjuvant) letrozole in combination with bevacizumab in post-menopausal women with newly diagnosed operable breast cancer: A preliminary safety report

11020

Background: Our preclinical studies suggest that up-regulation of tumor cell VEGF is a mechanism to subvert estrogen dependence in hormone responsive breast cancer resulting in reduced efficacy or acquired resistance; we hypothesized that the combination of Bevacizumab (an anti-VEGF MoAb) and hormonal therapy would be more effective than hormonal therapy alone for breast cancer. Methods: Post-menopausal patients with ER and/or PR positive and Her-2-neu negative operable (T2–4a-c/N 0–2/M0) breast cancer were enrolled. Patients received letrozole (2.5 mg po daily) and Bevacizumab (15 mg/kg IV q 3 wks). Patients were reevaluated every 6 wks for a total of 24 wks; patients with CR/PR/SD in the first evaluation continued in the trial; after an additional 6 weeks of therapy patients with PD or SD were taken off-study and only patients with PR/CR completed 24 weeks of therapy. Definitive surgery was performed at the discretion of the surgeon no sooner than 4 wks after the last dose of bevacizumab. Patients continued letrozole while waiting for surgery. Up to December 2006, 27 patients have been enrolled with 13 patients too early to evaluate. Results: The 14 patients off-study had a median age of 63 years (range; 56 to 79) and an ECOG score of 0 for all patients. None of the patients received therapy for breast cancer before enrollment in the trial. 11 patients were stage II and 3 patients stage III. No treatment-related severe adverse events were seen. Treatment related toxicities were: grade 3 hypertension (n=1), grade 2 hypertension (n=7), grade 2 fatigue (n=2), grade 2 joint pain (n=3), grade 2 hot flashes (n=2), grade 1 proteinuria (n=1); 2 patients were taken off-study because of uncontrolled hypertension occurring on initial infusion of bevacizumab (not evaluable for efficacy). Of the 12 patients evaluable for response, 2 patients had pCR, 8 PR and 2 PD (at 9 weeks and 16 weeks). There have been no problems with wound healing or bleeding related to surgery or progressive disease while awaiting surgery. Conclusions: Combination letrozole and bevacizumab has substantial clinical efficacy and is well tolerated. The combination therapy will be evaluated in a randomized Breast Cancer Research Consortium Trial.

[Table: see text]

A phase I/II study of galiximab (an anti-CD80 monoclonal antibody) in combination with rituximab for relapsed or refractory, follicular lymphoma

BACKGROUND

Galiximab is a monoclonal antibody that targets CD80, a costimulatory molecule constitutively expressed on follicular and other lymphomas. Modest single-agent clinical activity and tolerability were demonstrated in a phase I study in relapsed or refractory, follicular non-Hodgkin's lymphoma (NHL). A phase I/II study was conducted to evaluate galiximab in combination with a standard course of rituximab. Safety, pharmacokinetics, and efficacy were evaluated.

PATIENTS AND METHODS

Patients with follicular NHL who had relapsed or failed primary therapy were enrolled. Rituximab-refractory patients (no response or a response with time to progression <6 months) were excluded. Patients received 4 weekly i.v. infusions of galiximab (125, 250, 375, or 500 mg/m(2)) and rituximab (375 mg/m(2)). International Workshop Response Criteria (IWRC) were used to evaluate response.

RESULTS

Seventy-three patients received treatment. All had received at least one prior lymphoma therapy; 40% were rituximab naive. Infusions were delivered in an outpatient setting and were well tolerated. The most common study-related adverse events (AE) were lymphopenia, leukopenia, neutropenia, fatigue, and chills. The overall response rate at the recommended phase II dose of galiximab (500 mg/m(2)) was 66%: 19% complete response, 14% unconfirmed complete response, and 33% partial response. The median progression free survival was 12.1 months. Combination therapy did not appear to alter pharmacokinetics.

CONCLUSION

These results indicate that galiximab can be safely combined with a standard course of rituximab. This doublet biologic approach offers the potential to avoid or delay chemotherapy or to integrate with other lymphoma therapies. A phase III, randomized study evaluating clinical benefit of rituximab versus the combination has been initiated.

Phase II study of volociximab (M200), an α5β1 anti-integrin antibody in metastatic melanoma

8011

Background: Integrin α5β1 has been reported to be unregulated in metastatic melanoma and in tumor angiogenesis. A critical survival step in angiogenesis is the ligation of fibronectin in the extracellular matrix to α5β1 on endothelial cells. M200 is an IgG4 chimeric monoclonal antibody targeting α5β1, inducing apoptosis of proliferating endothelial cells. M200 activity is independent of growth factor stimulus, suggesting that binding of fibronectin to α5β1 occurs downstream of growth factor signalling, and is possibly a final common pathway for the development of neovasculature. Methods: This is a multicenter, open label, single cohort, pilot phase II study of 40 patients (pts) in metastatic melanoma. Pts received M200 10 mg/kg IV every 2 weeks with DTIC 1g/m2 monthly until disease progression. Pts were evaluated for efficacy every 8 weeks by objective response using RECIST criteria. Additional evaluations included pharmacokinetics and immunogenicity profile. An independent data safety monitoring board was utilized to review safety data. Results: A total of 40 pts have been enrolled to date. All pts were evaluable for safety and 30 pts for objective response using ITT population. Median age was 58.8 years, with 26 (65%) male. ECOG score was 0–1 in 37 (92%) pts. Up to 14 doses of M200 (median 4 doses) and 7 doses of DTIC (median 2) have currently been administered, with dosing continuing. Thirty-one (77.5%) pts have had at least 1 AE with 8 (20%) pts at least 1 SAE. The most frequent adverse events for M200 were nausea 17.5%, constipation 10% and vomiting 10% and for DTIC were nausea 35%, vomiting 20% and pyrexia 15%. Fifteen SAE’s with 2 possibly related to M200 including hypertension and deep vein thrombosis. Four pts died in the study, all with progressive disease (PD). Best overall response at 8 weeks was stable disease (SD) in 16/30 pts and PD in 14/30 pts. Median time to progression was 72 days. Conclusions: M200 appears to be well tolerated at 10 mg/kg Q2W in combination with DTIC.

[Table: see text]

A humanized antibody against CD40 (SGN-40) is well tolerated and active in non-Hodgkin’s lymphoma (NHL): Results of a phase I study

7534

Background: CD40 is a member of the TNF receptor family and is widely expressed on hematologic malignancies of B-cell origin. SGN-40 is a humanized antibody against CD40 with effector cell function and mild agonistic activity. Preclinical toxicity studies and efficacy data supported initiation of a multi-institutional phase I study to test the safety, pharmacokinetics, immunogenicity, and efficacy of SGN-40 in patients with relapsed NHL. Methods: Cohorts of 3–6 pts were treated weekly with a maximum dose of 2, 3, or 4 mg/kg/wk SGN-40. A dose escalation schedule is used such that patients receive 1 mg/kg on D1 and D4, 2 mg/kg on D8, and higher doses on weeks 3–5. Responding patients may receive a second cycle. Further dose escalation up to 8 mg/kg is planned. Results: 16 pts have been treated with multiple histologic subtypes: follicular (1), marginal zone (MZL; 1), mantle cell (4), and diffuse large B-cell (DLBCL; 10). One patient (2 mg/kg) developed a reversible Grade 3 unilateral conjunctivitis and ipsilateral loss of visual acuity. No other dose limiting toxicity has been observed up to 4 mg/kg. Preliminary pharmacokinetic data suggest that the antibody has a relatively short half-life, perhaps reflecting a route of elimination or binding that is not saturated at current doses. Two partial responses have been observed at 3 mg/kg (1 MZL, 1 DLBCL) and one partial response has been observed at 4 mg/kg dose (DLBCL relapsed after autologous stem cell transplant with small volume tumor). Conclusions: Using an intra-patient dose escalation schedule, SGN-40 has been well-tolerated at doses up to 4 mg/kg/wk. Further dose-escalation is ongoing to determine the maximum tolerated dose. Three objective responses have been seen, including two in patients with extensively treated aggressive disease. Correlative studies are underway measuring soluble CD40, cytokine release, effect of FcR polymorphisms, and SGN-40-induced immunogenicity. Given the favorable tolerability and activity, phase II studies in NHL are planned.

[Table: see text]

Lumiliximab with fludarabine, cyclophosphamide, and rituximab (FCR) for patients with relapsed chronic lymphocytic leukemia (CLL)

6597

Background: Lumiliximab, an anti-CD23 monoclonal antibody, had pharmacologic activity and an outstanding safety profile in a recently completed phase 1, single-agent study. Based on evidence of clinical activity, favorable safety profile, and preclinical data suggesting synergy with both fludarabine and rituximab, we initiated a combination study of lumiliximab with FCR in previously treated patients. Methods: Patients ≥18 years of age with relapsed CD23+ B-cell CLL were eligible for this open-label, dose-escalation, phase 1/2 study. Sample size was planned for ≤37 patients. Patients received either 375 mg/m2 or 500 mg/m2 of lumiliximab in combination with each 28-day cycle of FCR for 6 cycles. Primary objectives were to determine the safety profile, recommended phase 2 dose, and clinical activity of lumiliximab with FCR. Results: Accrual began in June 2004; 30 of the 31 patients were enrolled by December 2005; data are available for 28 patients. No dose-limiting toxicity was noted in the phase 1 component (375 mg/m2 dose, n=3, and 500 mg/m2 dose, n=6) and 500 mg/m2 was chosen for the phase 2 dose. All enrolled patients had progressive, symptomatic CLL as defined by NCI criteria, median 2 prior treatments (range, 1 to 9), median age 58, 64% males, 96% WHO performance status of ≤1. Seventeen patients experienced CTC Grade 3 or 4 adverse events (hematologic toxicity typically associated with FCR). Sixteen patients completed ≥3 cycles of treatment and were evaluated for response using NCI-WG criteria: 7 (44%) patients with confirmed complete responses (CRs); 1 with unconfirmed CR (pending marrow confirmation), 3 with partial responses (PRs), 4 with PRs awaiting confirmation, and 1 with disease progression. Twelve patients are not yet evaluable for response. Conclusions: Lumiliximab in combination with FCR is well tolerated and may enhance the activity of FCR for treatment of patients with progressive CLL after prior therapy.

[Table: see text]