Alfred F. Trappey

Primary analysis of the prospective, randomized, phase II trial of GP2+GM-CSF vaccine versus GM-CSF alone administered in the adjuvant setting to high-risk breast cancer patients.

134 Background: GP2 is a HER2 derived, HLA-A2+-restricted immunogenic peptide designed to stimulate CD8+T cells to recognize tumor cells with any level of HER2 expression (IHC 1-3+). Accrual to a prospective, randomized, multi-center, phase II trial of the GP2 vaccine for prevention of breast cancer recurrence has completed. Here, the planned primary analysis of disease-free survival (DFS) is presented. METHODS HLA-A2+ node positive or high-risk node negative breast cancer patients (pts) with any level of HER2 expression rendered disease-free by standard of care therapy (to include trastuzumab where appropriate) were randomized to receive GP2+GM-CSF (VG) or GM-CSF (CG) alone. Pts received 6 monthly inoculations (primary vaccine series = PVS) followed by 4 boosters administered every 6 months. The Kaplan Meier method was used for statistical analysis. The intention-to-treat (ITT) population is defined as the entire randomly assigned population. The per-treatment (PT) group excluded pts who recurred during the PVS or developed a second malignancy. A pre-specified subgroup analysis was performed based on HER2 expression level. HER2 overexpression (OE) is defined as IHC 3+or FISH >2.2. RESULTS With 89 VG and 91 CG pts enrolled and vaccinated, there are no differences between groups with respect to age, node positivity, tumor size, grade, ER/PR status, and HER2 expression (p>0.05). The vaccine has been well tolerated with toxicities comparable between the VG and CG. Only one grade 3 local and systemic toxicity reaction has been reported in the VG. At 34 (1-60) month median follow-up, DFS was compared in the ITT (85% VG v 81% CG, p = 0.57) and PT (94% VG v 85% CG, p = 0.17) populations. In OE patients (51 VG and 50 CG) DFS was 94% VG v 89% CG, p = 0.86 (ITT) and 100% VG v 89% CG, p = 0.08 (PT). CONCLUSIONS GP2+GM-CSF is a novel vaccine that is safe and well tolerated. This phase II trial demonstrates potentially greater benefit in pts with HER2 OE tumors, in whom there have been no recurrences in the PT group. This may be due to synergism with trastuzumab therapy, thus justifying a phase III trial evaluating GP2 administered in the adjuvant setting to a HER2 OE population. CLINICAL TRIAL INFORMATION NCT00524277.

Analysis of Clinical and Pathologic Factors of Pure, Flat Epithelial Atypia on Core Needle Biopsy to Aid in the Decision of Excision or Observation

Background: The optimal treatment of flat epithelial atypia (FEA) found on breast core needle biopsy (CNB) is controversial. We performed a retrospective review of our institutional experience with FEA to determine if excisional biopsy may be deferred. Methods: Surgical records from 2009 to 2012 were reviewed for FEA diagnosis. After exclusion for concomitant lesions, CNBs of pure FEA were classified using a previously agreed upon descriptor of “focal” versus “prominent”. Data was analyzed with the Fishers Exact and Student-t test as appropriate. Results: Of 71 CNBs evaluated, pure FEA was identified on 27 CNBs. Final excisional biopsy was benign in 24 of 27 cases (88%) with associated ductal carcinoma in-situ (DCIS) in 3 of 27 cases (11%). Eighteen of 27 (67%) CNBs were classified as focal while 9 (33%) were described as prominent. Zero of the 18 focal patients had a malignancy compared to 3 of the 9 in the prominent group (0% vs 33%, p=0.02). Of the 27 pure FEA CNBs, 6 patients had a personal history of breast carcinoma, five DCIS and one invasive ductal carcinoma. No malignancies were found in the 21 patients without a personal history of breast carcinoma versus three in the patients with a positive history (0/21 v 3/6, p=0.007). Conclusions: Our data suggests those women who have adequate sampling and sectioning of CNBs, with focal, pure FEA on pathology, and are without a personal history of breast cancer may undergo a period of imaging surveillance. Conversely, patients with a history of breast cancer or pure, prominent FEA on CNB disease should proceed to excisional biopsy.

Cancer vaccines in colon and rectal cancer over the last decade: lessons learned and future directions

ABSTRACT Introduction: Great advances have been made in screening for and treatment of colorectal cancer (CRC), but recurrence rates remain high and additional therapies are needed. There is great excitement around the field of immunotherapy and many attempts have been made to bring immunotherapy to CRC through a cancer vaccine. Areas covered: This is a detailed review of the last decade’s significant CRC vaccine trials. Expert commentary: Monotherapy with a CRC vaccine is likely best suited for adjuvant therapy in disease free patients. Vaccine therapy elicits crucial tumor infiltrating lymphocytes, which are lacking in microsatellite-stable tumors, and therefore may be better suited for these patients. The combination of CRC vaccines with checkpoint inhibitors may unlock the potential of immunotherapy for a much broader range of patients. Future studies should focus on vaccine monotherapy in correctly selected patients and combination therapy in more advanced disease.

Interim analysis of a phase I/IIa trial assessing E39+GM-CSF, a folate binding protein vaccine, to prevent recurrence in ovarian and endometrial cancer patients

BACKGROUND Folate binding protein(FBP) is an immunogenic protein over-expressed in endometrial(EC) and ovarian cancer(OC). We are conducting a phase I/IIa trial of E39 (GALE 301)+GM-CSF, an HLA-A2-restricted, FBP-derived peptide vaccine to prevent recurrences in disease-free EC and OC patients. This interim analysis summarizes toxicity, immunologic responses, and clinical outcomes to date. METHODS HLA-A2+ patients were vaccinated(VG), and HLA-A2- or -A2+ patients were followed as controls(CG). Six monthly intradermal inoculations of E39+250mcg GM-CSF were administered to VG. Demographic, safety, immunologic, and recurrence rate(RR) data were collected and evaluated. RESULTS This trial enrolled 51 patients; 29 in the VG and 22 in the CG. Fifteen patients received 1000mcg E39, and 14 received <1000mcg. There were no clinicopathologic differences between groups(all p = 0.1). E39 was well-tolerated regardless of dose. DTH increased pre- to post-vaccination (5.71.5 mm vs 10.33.0 mm, p = 0.06) in the VG, and increased more in the 1000mcg group (3.82.0 mm vs 9.53.5 mm, p = 0.03). With 12 months median follow-up, the RR was 41% (VG) vs 55% (CG), p = 0.41. Among the 1000mcg patients, the RR was 13.3% vs 55% CG, p = 0.01. Estimated 2-year DFS was 85.7% in the 1000mcg group vs 33.6% in the CG (p = 0.021). CONCLUSIONS This phase I/IIa trial reveals that E39+GM-CSF is well-tolerated and elicits a strong, dose-dependent in vivo immune response. Early efficacy results are promising in the 1000 mcg dose cohort. This study proves the safety and establishes the dose of E39 for a larger prospective, randomized, controlled trial in HLA-A2+ EC and OC patients to prevent recurrence.

Vaccine-specific T-cell proliferation in response to a dual peptide cancer vaccine in breast and ovarian cancer patients

Meeting abstracts HER2 is a commonly expressed tumor-associated antigen in breast (BrCa) and, therefore, an attractive target for immunotherapy. We have investigated HER2-derived peptides as vaccines mixed with GM-CSF to include GP2 (a HLA-A2 and HLA-A3 restricted, CD8+ eliciting epitope) and AE37

Abstract 4670: Delayed urticarial reactions in the phase II trial of HER2/neu peptide vaccines + GM-CSF vs. GM-CSF alone in high risk breast cancer patients.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC We are conducting a phase II trial evaluating two HER2-specific vaccines (AE37 and GP2) in the adjuvant setting for the prevention of breast cancer (BC) recurrence. We have observed the development of delayed urticarial reactions (DURs) in several patients after inoculation. In this report, we characterize the DURs and analyze immunologic responses (IR) in this population. After completion of standard of care therapy, disease-free, node-positive or high-risk node-negative BC patients (pts) with any level of HER2 expression (IHC1-3+) were randomized to receive either a peptide+GM-CSF (VG) or GM-CSF (CG). Pts receive 6 monthly intradermal inoculations during the primary vaccine series (PVS) followed by four boosters (B) every 6 mos. IR were measured by local reaction (LR) and delayed type hypersensitivity (DTH) pre (R0) and post-PVS (R6). Ten (4.3%) of a total 231 initiated pts have had a DUR; 5 in VG (vDUR) (3AE37, 2 GP2), and 5 in CG (cDUR). Median time to onset of symptoms was the same for cDUR/vDUR (median 8 days (d); range, 0-17 d). All DUR pts described generalized pruritis/hives, with two also having difficulty swallowing/globus. Symptoms resolved with IV/oral steroids (n=4), oral steroids only (n=3), or antihistimines (n=3). Duration ranged from 4 d-4 mos with a median of 21 d. vDUR pts had a longer median duration of symptoms than cDUR pts (105 d v 9 d, p=0.02). Four pts (3 vDUR, 1 cDUR) had recurrent symptoms that resolved after treatment similar to above. The majority of events (9) occurred between B1 and B3, but one event did occur after the first inoculation. All DUR pts have received no further inoculations. Comparing pts who have had a DUR to those who have not (noDUR), there were no significant differences in age, tumor size/grade, HER2 expression, or ER/PR status. 70% of DUR pts have environmental allergies. No other risk factor has been identified. vDUR pts had weaker IR than VG noDUR (LR- R0: 21v36mm, p=0.14; R6: 30v57mm, p=0.17) (DTH - R0: 0.6v2mm, p=0.25; R6: 17v25mm, 0.21). cDUR pts had stronger IR than CG noDUR (LR - R0: 46v1mm, p=0.005; R6: 93v50mm, p=0.01) (DTH - R0: 9.1v2.3mm, p=0.003; R6: 15.3v5mm, p=0.03). There have been no recurrences in the DUR group compared to 11.4% in the noDUR group (p=0.26). DUR has occurred infrequently with no long-term sequelae. DURs have occurred evenly between vDUR and cDUR indicating GM-CSF is the likely cause. Stronger IR in the cDUR group suggest that these ptss immune system may have a predisposition toward a more robust response to GM-CSF. Less robust DTH/LR as well as longer symptom duration in the vDUR suggest the vaccine may potentiate non-specific systemic immune activation in some pts. We plan to further characterize DUR in our ongoing trial. Citation Format: Alfred F. Trappey, John S. Berry, Timothy J. Vreeland, Diane F. Hale, Alan K. Sears, Guy Clifton, Sathibalan Ponniah, Michael Papamichail, Sonia A. Perez, Elizabeth Mittendorf, George E. Peoples. Delayed urticarial reactions in the phase II trial of HER2/ neu peptide vaccines + GM-CSF vs. GM-CSF alone in high risk breast cancer patients. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4670. doi:10.1158/1538-7445.AM2013-4670

Abstract CT162: Pre-specified interim analysis in a prospective, randomized phase II trial of trastuzumab vs trastuzumab + NeuVax to prevent breast cancer recurrence in HER2+ breast cancer patients

Introduction: The HER2-targeted monoclonal antibody, trastuzumab (Tz), is standard of care (SOC) for HER2-positive (HER2+) breast cancer (BCa) and has been shown to reduce recurrence. We have previously shown that NeuVax (E75 peptide + GM-CSF), a HER2-targeted peptide vaccine, is safe, immunogenic, and may have synergistic clinical efficacy when combined with Tz. Given the known cardiac toxicity of Tz, there is concern that adding a HER2-directed vaccine to Tz therapy may exacerbate this effect. We are currently enrolling patients (pts) in a multi-center, prospective, randomized, single-blinded, placebo-controlled phase II trial combining Tz and Neuvax in the adjuvant setting to prevent recurrence in HER2+ BCa pts. Here, we present the initial safety data. Methods: HLA-A2/A3+ BCa pts with stage I-III HER2+ disease at high risk for recurrence (pts not achieving complete response after Tz-containing neoadjuvant therapy or those undergoing up-front surgery with any node-positive disease if ER/PR- or ≥4 positive nodes if ER/PR+) were enrolled after SOC surgery, radiation and neo-adjuvant/adjuvant chemotherapy with approved Tz-containing regimen. Pts were randomized to receive Tz and NeuVax in the vaccine group (VG) or Tz and GM-CSF only in the control group (CG). Pts received vaccinations of NeuVax or GM-CSF intradermally every 3 weeks for 6 total vaccinations (primary vaccine series, PVS) starting with the third dose of Tz maintenance therapy. Starting 6 months after the completion of the PVS, pts received four booster inoculations, one every 6 months. Cardiac ejection fraction (EF) was assessed by either echo or MUGA at baseline and serially during treatment. Demographic and safety data were collected and analyzed. Safety analysis was initiated after enrollment of the 50th patient. Results: To date, we have enrolled 50 pts (VG n=22, CG n=28). There were no significant clinicopathologic differences between groups. There were no related grade 4 or 5 toxicities and no differences in related toxicities between the VG and CG (Grade 1: 96% vs 98.5%; Grade 2: 3.2% vs 1.5%; Grade 3: 0.8% vs 0%, p=0.14). There was no significant reduction in EF pre- to post-treatment in either group (VG: 61.1±5.4% vs 60.1±4.8%, p=0.55; CG: 62.3±5.7% vs 61.9±4.0%, p=0.74) and there was no difference in change between groups (p=0.54). Conclusion: The combination of Tz and Neuvax in HER2+ BCa pts is well tolerated and the cardiac effects from Tz are not worsened by the addition of NeuVax. We will continue to enroll up to our goal of 100 pts in this ongoing trial, and will report immunologic and clinical outcomes in the planned primary analysis after 24-months follow-up. Citation Format: Kaitlin M. Peace, Jennifer K. Litton, Rashmi Murthy, Timothy J. Vreeland, Diane F. Hale, Doreen O. Jackson, John S. Berry, Alfred F. Trappey, Garth S. Herbert, Guy T. Clifton, Mark O. Hardin, George E. Peoples, Elizabeth A. Mittendorf. Pre-specified interim analysis in a prospective, randomized phase II trial of trastuzumab vs trastuzumab + NeuVax to prevent breast cancer recurrence in HER2+ breast cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT162. doi:10.1158/1538-7445.AM2017-CT162

Abstract B007: Improved disease-free survival in endometrial and ovarian cancer patients with low folate binding protein expression after treatment with the E39 peptide vaccine in a Phase I/IIa trial

Introduction: One of the most encouraging examples of targeted therapy for cancer is trastuzumab, but its success is dependent on levels of expression of its target, HER2. We have found that HER2 expression levels also have a significant impact on the efficacy of HER2-directed peptide vaccines. Analogous to HER2 in breast cancer, Folate Binding Protein (FBP) is over-expressed on ovarian and endometrial cancer cells (up to 80 - 90-fold higher) and increased FBP expression is associated with aggressive disease. As a result, multiple FBP-directed therapies are being developed. We are investigating E39 + GM-CSF, which is an HLA-A2-restricted FBP-derived peptide vaccine used to prevent recurrence in disease-free endometrial and ovarian cancer patients (pts) after standard of care (SOC), multi-modality therapy. We have shown that E39 is safe, effectively generates E39-specific immune responses, and may improve DFS when optimally dosed in a phase I/IIa trial.1 Little is known about the effects of FBP expression levels on FBP-directed therapies, including our E39 vaccine. Purpose: Here, we report clinical outcomes of patients based on FBP expression levels from a phase I/IIa trial of the E39+GM-CSF vaccine given for the prevention of recurrence in disease-free endometrial and ovarian cancer patients. Methods: Disease-free, HLA-A2+ pts were vaccinated (VG), while HLA-A2- pts were followed as untreated controls (CG). The VG received 6 monthly inoculations of E39+GM-CSF, including either 100, 500, or 1000mcg of peptide and 250mcg of GM-CSF. FBP expression testing was performed by immunohistochemistry and the results were graded 0-4+ based on the percentage of positively staining cells. Patient9s tumors were then categorized as low expression (FBPlo) if scored 0-1+ or high expression (FBPhi) if 2-4+. The pts were monitored for evidence of clinical recurrence through the SOC follow-up by their treating oncology team. Demographics, FBP expression and disease-free survival (DFS) were analyzed using appropriate statistical tests. Results: Thirty-eight enrolled pts underwent FBP expression testing (CG n = 20; VG n = 18). There were no clinicopathologic differences between groups (p≥0.1). Nineteen pts were found to be FBPlo (CG, n = 11; VG, n = 8) and 19 were FBPhi (CG, n = 9; VG, n = 10). Median follow up was 16.3 months. There was no significant difference in overall DFS between the CG and the VG (34.6% vs. 34.6%, p = 0.208). In FBPlo pts, there was improved DFS in the VG vs. CG (85.7% vs. 17.5%, p = 0.01) while there was no such difference in FBPhi pts (VG:13.9% vs. CG:44.4%, p = 0.83). Though groups were small, there was a dose-dependent effect on DFS; pts receiving 1000mcg (n = 4) had improved DFS compared to the Conclusion: This phase I/IIa trial has previously demonstrated that E39 is well-tolerated, elicits a strong, dose-dependent in vivo immune response and may improve DFS when properly dosed. This focused analysis based on FBP expression level revealed a DFS benefit in FBPlo, but not FBPhi, endometrial and ovarian cancer pts treated with E39. This may be due to immunotolerance from significantly higher endogenous exposure to the FBP antigen. This is concordant with findings in our trials of HER2-directed peptide vaccines in breast cancer pts. These findings warrant further study as they may have important implications regarding the target population for future E39 peptide vaccine trials. 1. Jackson DO, et al. Interim analysis of a phase I/IIa trial assessing E39+GM-CSF, a folate binding protein vaccine, to prevent recurrence in ovarian and endometrial cancer patients. In Press. Citation Format: Kaitlin M. Peace, Diane F. Hale, Timothy J. Vreeland, Doreen O. Jackson, Julia M. Greene, John S. Berry, IV, Alfred F. Trappey, Garth S. Herbert, Guy T. Clifton, Mark O. Hardin, Kathleen M. Darcy, Chad A. Hamilton, G. Larry Maxwell, George E. Peoples. Improved disease-free survival in endometrial and ovarian cancer patients with low folate binding protein expression after treatment with the E39 peptide vaccine in a Phase I/IIa trial [abstract]. In: Proceedings of the Second CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; 2016 Sept 25-28; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(11 Suppl):Abstract nr B007.

Preliminary report of a clinical trial supporting the sequential use of an attenuated E39 peptide (E39') to optimize the immunologic response to the FBP (E39+GM-CSF) vaccine

Meeting abstracts Folate Binding Protein (FBP) is overexpressed in breast, endometrial, and ovarian cancers. E39 (FBP191-199, EIWTHSYKV) is an HLA-A2 restricted FBP peptide vaccine already shown to generate significant in vivo immunologic response (IR) in a Phase I/IIa trial in endometrial and

Abstract OT3-1-09: Combination immunotherapy with trastuzumab and the HER2 vaccine E75 (nelipepimut-S) in high-risk HER2+ breast cancer patients to prevent recurrence

Background: In an adjuvant phase II trial, the HER2-derived nelipepimut-S (E75) + GM-CSF vaccine (Neuvax) has been shown to reduce breast cancer recurrence. Preclinical testing of the combination of trastuzumab (Tz) and nelipepimut-S has shown synergistic cytolysis against HER2 expressing cancer cells. In pilot phase II data in HER2+ patients (pts), 55 pts dosed with CD8-eliciting HER2 derived peptide vaccines sequentially after treatment with Tz resulted in no recurrences at 36 months median follow-up compared with a 16% recurrence rate in 34 randomized controls treated with Tz without vaccine (p=.012). Based on these data, we have designed a trial to evaluate the ability of the combination of Tz and the E75 vaccine concurrently to prevent recurrence in pts with high-risk, HER2+ breast cancer. Trial Design: This study will be a multicenter, prospective, randomized, single-blinded, phase II trial evaluating adjuvant Tz + NeuVax (E75+GM-CSF) vs. Tz + GM-CSF alone in high-risk HER2+ (IHC 3+ and/or FISH >2.2) breast cancer pts. High-risk pts include: 1) those that did not achieve a pathologic complete response (pCR) after neoadjuvant chemotherapy and HER2- targeted therapy or 2) those treated with upfront surgery that are node positive (> 4+ LN or 1-3+ LN if hormone receptor negative). Pts must be HLA-A2 /A3+ to be eligible (E75 is HLA-A2/A3-restricted) with ECOG performance status 0-1. Pts will be enrolled after completing standard of care multi-modal therapy but prior to the 3rd dose of Tz maintenance therapy (monotherapy). Pts will be randomized 1:1 to receive either NeuVax or GM-CSF alone which will be administered as six monthly intradermal inoculations concurrently with Tz therapy. Pts will then receive four booster inoculations of either NeuVax or GM-CSF every 6 months. The primary efficacy endpoint is to compare disease-free survival (DFS) between treatment arms. Secondary objectives will include evaluation of local and systemic toxicity, distant recurrence free survival, and in vivo/in vitro immunologic responses. From previously published experience with Tz, we expect a recurrence rate of 20% in Tz (plus GM-CSF) treated pts and anticipate that the combination of Tz with E75+GM-CSF will reduce this recurrence rate to 5%. In order to show statistical difference between these recurrence rates, we plan to enroll 50 pts per treatment arm (100 total) with a type I error rate of 5% and 80% power to detect the primary endpoint. Trial accrual is anticipated to begin in September of 2014, with a two year period for trial enrollment followed by a three year follow-up period. Conclusion: We hypothesize that combination adjuvant immunotherapy with Tz and NeuVax will result in a greater reduction in breast cancer recurrence than Tz therapy alone. We have designed a prospective, randomized, single-blinded, phase II trial evaluating the efficacy of this immunotherapy combination in high-risk HER2+ breast cancer pts to test this hypothesis. Contact Information: This trial is funded by a DoD grant to EAM with matching funds from Galena Biopharma and is being conducted with the assistance of the academic CRO, Cancer InCITe, LLC. Citation Format: Beth A Mittendorf, Erika J Schneble, Nuhad K Ibrahim, Julia M Greene, John S Berry, Alfred F Trappey, Guy T Clifton, Jarrod P Holmes, Sathibalan Ponniah, George E Peoples. Combination immunotherapy with trastuzumab and the HER2 vaccine E75 (nelipepimut-S) in high-risk HER2+ breast cancer patients to prevent recurrence [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr OT3-1-09.