A phase I open-label, dose-escalation study of NUC-3373, a targeted thymidylate synthase inhibitor, in patients with advanced cancer (NuTide:301)

PURPOSE

5-fluorouracil (5-FU) is inefficiently converted to the active anti-cancer metabolite, fluorodeoxyuridine-monophosphate (FUDR-MP), is associated with dose-limiting toxicities and challenging administration schedules. NUC-3373 is a phosphoramidate nucleotide analog of fluorodeoxyuridine (FUDR) designed to overcome these limitations and replace fluoropyrimidines such as 5-FU.

PATIENTS AND METHODS

NUC-3373 was administered as monotherapy to patients with advanced solid tumors refractory to standard therapy via intravenous infusion either on Days 1, 8, 15 and 22 (Part 1) or on Days 1 and 15 (Part 2) of 28-day cycles until disease progression or unacceptable toxicity. Primary objectives were maximum tolerated dose (MTD) and recommended Phase II dose (RP2D) and schedule of NUC-3373. Secondary objectives included pharmacokinetics (PK), and anti-tumor activity.

RESULTS

Fifty-nine patients received weekly NUC-3373 in 9 cohorts in Part 1 (n = 43) and 3 alternate-weekly dosing cohorts in Part 2 (n = 16). They had received a median of 3 prior lines of treatment (range: 0-11) and 74% were exposed to prior fluoropyrimidines. Four experienced dose-limiting toxicities: two Grade (G) 3 transaminitis; one G2 headache; and one G3 transient hypotension. Commonest treatment-related G3 adverse event of raised transaminases occurred in < 10% of patients. NUC-3373 showed a favorable PK profile, with dose-proportionality and a prolonged half-life compared to 5-FU. A best overall response of stable disease was observed, with prolonged progression-free survival.

CONCLUSION

NUC-3373 was well-tolerated in a heavily pre-treated solid tumor patient population, including those who had relapsed on prior 5-FU. The MTD and RP2D was defined as 2500 mg/m2 NUC-3373 weekly. NUC-3373 is currently in combination treatment studies.

TRIAL REGISTRATION

Clinicaltrials.gov registry number NCT02723240. Trial registered on 8th December 2015. https://clinicaltrials.gov/study/NCT02723240 .

Abstract CT155: Clinical biomarker studies with an enhanced potency oncolytic HSV expressing an anti-CTLA-4 antibody, as a single agent and combined with nivolumab in patients with advanced solid tumors indicates potent immune activation

Introduction: RP2 is a novel, enhanced potency oncolytic HSV1 which expresses GM-CSF, an anti-CTLA-4 antibody-like molecule and the fusogenic gibbon ape leukemia virus membrane R- glycoprotein (GALV-GP R-). RP2 is in clinical development in a range of solid tumors alone and with nivolumab (nivo). RP2 + nivo has resulted in deep and durable responses in patients who failed prior anti-PD1 therapy (SITC 2021). Here we present biomarker data in patients treated with RP2 alone or combined with nivo from an ongoing clinical trial (NCT04336241).

Methods: Tumor biopsies and peripheral blood mononuclear cells (PBMCs) were collected pre-treatment and at D43. The tumor immune microenvironment (TIME) was analyzed by multi-plex (7 color 6-plex - CD8, PD-L1, PD-1, foxp3, CD68 and S100B) immunohistochemistry (IHC) of tumor biopsies using the Opal Human Panel (OHP) 6043 and by gene expression analysis using the NanoString IO360 panel. The tumor inflammation signature score (TIS) was also calculated using an 18 gene signature (Ayers JCI 2017) . Systemic anti-tumor immunity was assessed using PBMCs by sequencing the CDR3 regions of TCRβ chains using immunoSEQ Assay. Correlation analysis of baseline tumor PD-L1 and CD8 status versus clinical responses was also performed.

Results: IHC indicated robust increases in CD8 T cell influx and PD-L1 expression post-RP2 alone and with RP2 + nivo. An increase in the CD8/foxp3+ cell ratio was observed by multi-plex IHC. A consistent increase in CD8 and PD-L1 was observed in most of the tested biopsies (~70%), which generally appeared to be co-located (n=20). These increases in CD8 and PD-L1 expression levels were observed in both superficial and visceral tumors. A particularly striking change was observed in a biopsy obtained from a liver lesion from a tebantafusp and ipi/pembro-failed uveal melanoma patient. Clinical responses were independent of baseline CD8 T cell infiltration, PD-L1 expression levels, and prior anti-PD-1 therapy status. Gene expression analysis of tumor biopsies (n=12) indicated increases in the expression of key genes associated with immune activation, particularly those associated with dendritic cell function, major histocompatibility complex-II and interferon-gamma signature. Increases in expression of genes associated with ARG1, cytotoxicity, IDO1, NK cell and Th1 cell abundance were observed, particularly in responding patients. TCR sequencing of PBMCs revealed expansion of pre-existing T cell clones and the appearance of new clones post-RP2 monotherapy and RP2 + nivo, with ~50% of these changes being newly detected clones. Expansion of pre-existing clones and generation of new T cell clones specific for MART-1 was also observed with RP2 monotherapy and in combination.

Conclusion: The biomarker data presented indicates broad immune activation by RP2 and demonstrates that clinical response does not correlate with baseline PD-L1 and CD8 expression status. Clinical responses were often associated with increases in gene signatures associated with cytotoxic T, NK and Th1 cells. These data indicate the potential for broad utility of RP2 in a range of tumor types, including in patients with primary or acquired resistance to immune checkpoint blockade.

Citation Format: Kevin J. Harrington, Praveen K. Bommareddy, Mark R. Middleton, Joseph J. Sacco, Anna Olsson-Brown, Tze Y. Chan, Pablo Nenclares, Isla Leslie, Francesca Aroldi, Imran Saleem, Christoph M. Ahlers, Henry Castro, Robert S. Coffin. Clinical biomarker studies with an enhanced potency oncolytic HSV expressing an anti-CTLA-4 antibody, as a single agent and combined with nivolumab in patients with advanced solid tumors indicates potent immune activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT155.

Lag3: From Bench to Bedside

The introduction of immune checkpoint inhibitors represented a breakthrough treatment for metastatic melanoma, but the effect of these agents is not limited to a single cancer type. Promising results have been reported in various solid tumors, for example, lung cancer. The success of these drugs depends on the activation of tumor-infiltrating lymphocytes and primary and acquired resistance have been reported alongside a high rate of immune-related adverse events when agents targeting different immune checkpoints are given in combination. Numerous other targets have been investigated to overcome the resistance, improve the activity, and reduce the toxicity of checkpoint inhibitor therapy. Among these, the most promising is Lymphocyte-activation gene 3 (LAG-3), a transmembrane protein involved in cytokine release and inhibitory signaling in T cells. Preclinical data showed that LAG-3 is a negative regulator of both CD4⁺ T cell and CD8⁺ T cell and the activity on CD8⁺ T cell is independent of CD4⁺ activation. On the CD8⁺ T cell, LAG-3 activation abrogates the antigen presentation whereas on the CD4⁺ T cell, arrests the S phase of the cell cycle. The blockade of LAG-3 has been tested in several combination therapies, and recent clinical data showed a good safety profile and a synergistic effect with anti-PD-1, suggesting that this combination could become a standard treatment for metastatic melanoma. In this review, we report the available preclinical data and the new clinical data on LAG-3 blockade in different solid tumors, and we discuss LAG-3 as potential prognostic and predictive factor, together with possible future applications.

Long-Term Outcomes of Immune Checkpoint Inhibition in Metastatic Melanoma

Increasing knowledge about the biology of melanoma and of immunology has led to the development and regulatory approval of the immune checkpoint inhibitors ipilimumab, nivolumab, and pembrolizumab, which are indicated for the treatment of melanoma irrespective of the B-Raf proto-oncogene mutation status of the tumour. Only a subset of patients will respond, but those who do can expect long-lasting, previously unheard-of responses. Long-term survival results for the registration trials, including CheckMate 067, Keynote-006, and Keynote-001, have recently been published. In particular, the combination of ipilimumab and nivolumab showed an impressive 5-year overall survival of just over 50%. However, toxicity remains a significant concern, with some of the side effects being life threatening and/or life changing. In this review, we discuss the safety and efficacy data of all the agents currently approved for the first-line treatment of advanced melanoma, identifying factors that influence the choice of a single agent rather than combination therapy. We highlight the potential biomarkers of response, effects of long-term toxicity, and options after progression.

CHK1 inhibition exacerbates replication stress induced by IGF blockade

We recently reported that genetic or pharmacological inhibition of insulin-like growth factor receptor (IGF-1R) slows DNA replication and induces replication stress by downregulating the regulatory subunit RRM2 of ribonucleotide reductase, perturbing deoxynucleotide triphosphate (dNTP) supply. Aiming to exploit this effect in therapy we performed a compound screen in five breast cancer cell lines with IGF neutralising antibody xentuzumab. Inhibitor of checkpoint kinase CHK1 was identified as a top screen hit. Co-inhibition of IGF and CHK1 caused synergistic suppression of cell viability, cell survival and tumour growth in 2D cell culture, 3D spheroid cultures and in vivo. Investigating the mechanism of synthetic lethality, we reveal that CHK1 inhibition in IGF-1R depleted or inhibited cells further downregulated RRM2, reduced dNTP supply and profoundly delayed replication fork progression. These effects resulted in significant accumulation of unreplicated single-stranded DNA and increased cell death, indicative of replication catastrophe. Similar phenotypes were induced by IGF:WEE1 co-inhibition, also via exacerbation of RRM2 downregulation. Exogenous RRM2 expression rescued hallmarks of replication stress induced by co-inhibiting IGF with CHK1 or WEE1, identifying RRM2 as a critical target of the functional IGF:CHK1 and IGF:WEE1 interactions. These data identify novel therapeutic vulnerabilities and may inform future trials of IGF inhibitory drugs.

507 A phase 1 clinical trial of RP2, an enhanced potency oncolytic HSV expressing an anti-CTLA-4 antibody, as a single agent and combined with nivolumab in patients with advanced solid tumors

Background

RP2 is a first-in-class, enhanced potency oncolytic herpes simplex virus (HSV) -1 expressing GM-CSF, a fusogenic protein (GALV-GP R-), and an anti-CTLA-4 antibody-like molecule that is being tested in an open-label, multicenter, phase 1 study alone and combined with nivolumab (nivo). Preliminary data with RP2 as monotherapy has been presented previously [1–2]. We present updated safety, tolerability, and clinical activity data of RP2 alone and initial data in combination with nivolumab.

Methods

Using a 3+3 dose escalation, patients (pts) received intratumoral injections of up to 10 mL RP2 to superficial and/or visceral tumors Q2W up to 5 times at two dose levels (Dose level 1: 10^5 PFU/mL then 4 doses of 10^6 PFU/mL; dose level 2: 10^6 PFU/mL then 4 doses of 10^7 PFU/mL). Following determination of the RP2D (10^6 PFU/mL, followed by subsequent doses of 10^7 PFU/mL, Q2W X 7), a combination cohort of 30 pts were dosed with RP2 up to 8 times combined with nivo (240 mg Q2W for 4 mos from the second RP2 dose, then 480 mg Q4W for 20 mos). Re-initiation of up to 8 additional RP2 doses is permitted in prespecified circumstances.

Results

Nine pts were enrolled into the RP2 monotherapy phase (6 seropositive and 3 seronegative for HSV). Objective responses were observed in 3 pts, 1 ongoing CR for ≥15 months in mucoepidermoid carcinoma, 1 ongoing PR for ≥18 months in esophageal cancer with liver metastases, 1 PR in uveal melanoma with liver metastases that progressed at 15 months. As of June 3rd 2021, 27 patients had been enrolled and ongoing partial responses had been observed in 4/9 anti-PD-1 failed cutaneous melanoma, 1/3 uveal melanoma and 1/3 SCCHN pts. A further 8 patients remained on study with the opportunity for response. Biomarker analyses indicate T cell infiltration, increase in tumor inflammation signature, expansion of existing T cell clones and emergence of new T cell clones, together indicative of local and systemic anti-tumor activity. The combination was well tolerated and no new safety signals were identified.

Conclusions

RP2 ± nivo demonstrated good tolerability and durable systemic responses in pts with difficult-to-treat, heavily pretreated and anti-PD-1 failed advanced cancers. These data continue to support the hypothesis that oncolytic delivery of anti-CTLA-4 into tumors, with accompanying antigen release, presentation and immune activation, can provide potent systemic anti-tumor effects. Updated data from the full 30 patient cohort will be presented.

Trial Registration

NCT04336241

References

Aroldi F, Sacco J, Harrington K, Olsson-Brown A, Nanclares P, Menezes L, Bommareddy P, Thomas S, Kaufman H, Samakoglu S, Coffin R and Middleton M. 421, Initial results of a phase 1 trial of RP2, a first in class, enhanced potency, anti-CTLA-4 antibody expressing, oncolytic HSV as single agent and combined with nivolumab in patients with solid tumors Journal for Immuno Therapy of Cancer 2020;8.

Harrington KJ, Aroldi F, Sacco JJ, Milhem MM, Curti B, Vanderwalde A, et al. LB180-Clinical biomarker studies with two fusion-enhanced versions of oncolytic HSV (RP1 and RP2) alone and in combination with nivolumab in cancer patients indicate potent immune activation. Cancer Res 2021. LB-180

Ethics Approval

The study was approved by institutional review board or the local ethics committee at each site. Informed consent was obtained from patients prior to enrollment.

506 IGNYTE: an open-label, multicenter, phase 1/2 (Ph 1/2) clinical trial of RP1 ± nivolumab in patients with advanced solid tumors

Background

RP1 is an enhanced potency oncolytic HSV-1 which expresses a fusogenic glycoprotein (GALV-GP R-) and granulocyte macrophage colony stimulating factor (GM-CSF).1 In pre-clinical studies, RP1 demonstrated potent GALV-GP R-enhanced anti-tumor activity and immunogenic cell death. This Phase 1/2 (Ph 1/2) study was designed to evaluate the safety and efficacy of RP1 ± nivolumab (nivo) in patients (pts) with advanced solid tumors, including pts whose disease failed prior anti-PD-1/PD-L1 therapy and has reported promising interim data in a number of tumor types including cutaneous squamous cell carcinoma (CSCC) and anti-PD1 failed melanoma to date.2

Methods

This is a multi-center, first-in-human, open label, multi-cohort, non-randomized Ph1 study of RP1 alone and combined with nivo followed by Ph2 in combination with nivo in pts with recurrent advanced solid tumors including those that progressed after prior anti-PD-1/PD-L1 therapy. The Ph 1 monotherapy dose escalation (n=14) and RP-1 combination expansion (n=22) cohorts are fully enrolled. Approximately 260 pts are expected to be enrolled in the ongoing Ph 2 portion across five cohorts; melanoma (n=30, enrollment complete), non-melanoma skin cancer (n=45, to include 15 pts with anti-PD-1/PD-L1 failed disease), anti-PD-1 failed MSI-H/dMMR tumors (n=30), anti-PD-1/PD-L1-failed non-small-cell lung cancer (n=30) and a registration-directed cohort in anti-PD-1 failed cutaneous melanoma (n=125). Pts in the Ph 2 portion receive up to 10 mL of RP1 intratumorally into one or more superficial or deep seated/visceral lesions at the recommended Ph 2 dose (1x10^6 PFU/mL × 1 followed by 1x10^7 PFU/mL × 7, Q2W). Following the first dose of RP1, nivo (240 mg IV Q2W for 4 months then 480 mg IV Q4W for up to 2 years) is subsequently administered in combination. Pts may receive up to 8 additional doses of RP1 if they meet protocol-specified criteria. Tumor assessments are performed Q8W. The primary objectives of the Ph 2 part of the study are to assess the safety, tolerability, and overall response rate (ORR) of RP1 in combination with nivo, by independent review for the anti-PD1 failed melanoma cohort. Secondary objectives include duration of response, complete response rate, disease control rate, PFS, 1-year and 2-year survival rates. Exploratory objectives include biodistribution and shedding analysis of RP1 and biomarker studies, including analyses of tumor biopsies and blood samples. Enrollment is currently ongoing in the UK and US, with additional sites in the EU (including France and Spain) are expected to open in 2021.

Trial Registration

NCT03767348

References

Thomas S, Kuncheria L, Roulstone V, Kyula JN, Mansfield D, Bommareddy PK, Smith H, Kaufman HL, Harrington KJ, Coffin RS. Development of a new fusion-enhanced oncolytic immunotherapy platform based on herpes simplex virus type 1. J Immunother Cancer 2019;7(1):214.

Coffin R, Astley-Sparke P, and Middleton M (2021, June 3rd). Retrieved from https://ir.replimune.com/static-files/f4fe3349-e082-4d41-94a1-106ce7e78a23

Ethics Approval

The study was approved by institutional review board or the local ethics committee at each site. Informed consent was obtained from patients prior to enrollment.

Abstract CT136: NUC-7738, a novel ProTide transformation of 3′-deoxyadenosine, in patients with advanced solid tumors

Background: The novel ProTide NUC-7738 is a phosphoramidate transformation of 3'-deoxyadenosine (3'-dA or cordycepin), a derivative of adenosine that was first isolated from Cordyceps sinensis. The cytotoxic effect of 3'-dA is largely attributed to intracellular generation of the triphosphate metabolite, 3'-dATP, which inhibits DNA and RNA synthesis. Although 3'-dA has potent in vitro anti-tumor activity, it has not been successful in clinical studies due to its rapid breakdown by adenosine deaminase (ADA). NUC-7738 was designed to overcome the key cancer resistance mechanisms associated with 3'-dA. NUC-7738 is resistant to breakdown by ADA, enters cancer cells independently of the human equilibrative nucleoside transporter (hENT1) and it does not require adenosine kinase for phosphorylation. Methods: NuTide:701 is a two-part, first-in-human Phase I study in patients with advanced solid tumors or lymphoma who have exhausted all standard treatment options. The primary objective is to determine the recommended phase 2 dose (RP2D) and schedule of NUC-7738. Secondary objectives include safety, pharmacokinetics and anti-tumor activity. Part 1, in patients with advanced solid tumors, will establish the RP2D and schedule of NUC-7738. Part 2 will further evaluate NUC-7738 in expansion cohorts of patients with advanced solid tumors or lymphomas. Results: As of 25 Sept 2020, 15 patients had received escalating doses of 14-600 mg/m2 (IV infusion from 30-120 mins) NUC-7738 q1w in Part 1. Patients had received a mean of 3 prior lines of therapy (range: 1 to 5), with melanoma (n=5) and lung (n=3) the most common primary tumor types enrolled. NUC-7738 was well tolerated, with no Grade 3 or 4 treatment-related AEs. No dose-limiting toxicities have been reported. Encouraging signals of anti-cancer activity were observed in three patients who continued to receive clinical benefit for over 6 months (1 patient remained on treatment for over 17 months). NUC-7738 has a predictable plasma PK profile, with a dose proportional increase in Cmax and AUC. High intracellular levels of the anti-cancer metabolite 3'-dATP in PBMCs were detected 2 hours after the start of infusion and maintained for at least 24 hours. Conclusion: NUC-7738 has shown promising anti-cancer activity and a favorable tolerability profile in patients with advanced, treatment-refractory tumors. Patients had high and durable intracellular levels of the anti-cancer metabolite 3'-dATP, supporting non-clinical data that NUC-7738 overcomes the key cancer resistance mechanisms associated with 3'-dA.

Citation Format: Ruth Plummer, Farasat Kazmi, Noor Md Haris, Tze-en Ding, Francesca Aroldi, Michelle Myers, Stefan Symeonides, Sarah Blagden. NUC-7738, a novel ProTide transformation of 3′-deoxyadenosine, in patients with advanced solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT136.

Abstract LB180: Clinical biomarker studies with two fusion-enhanced versions of oncolytic HSV (RP1 and RP2) alone and in combination with nivolumab in cancer patients indicate potent immune activation

Introduction:RP1 and RP2 are novel, enhanced potency oncolytic versions of HSV1 engineered to express human GM-CSF and the gibbon ape leukemia virus membrane R- glycoprotein (GALV-GP R-), providing constitutive fusion activity and increased immunogenic cell death. RP2 further expresses an anti-CTLA-4 antibody-like molecule. Murine versions of RP1 and RP2 exhibited synergy in combination with anti-mouse-PD-1 leading to enhanced regression of both injected and un-injected tumors in mice (Thomas et al JITC 2019). RP1 and RP2 are currently being evaluated in clinical trials in a range of solid tumors alone and combined with anti-PD1 therapy, where deep and durable responses have been demonstrated (SITC 2020). Here we present biomarker data from the Phase 1/2 clinical trial of RP1 alone and combined with nivolumab (NCT03767348) and from the Phase 1 portion of the clinical trial with RP2 alone (NCT04336241).

Methods: In the Phase 1/2 studies tumor biopsies and peripheral blood mononuclear samples (PBMCs) were collected at screening and at D43 for biomarker analysis, after combination therapy with nivolumab for RP1 and following single agent treatment for RP2. Immunohistochemistry (IHC) was performed for CD8 (SP57 clone, Ventana) and for PD-L1 (28-8 clone, pharmDx assay). Gene expression was analysed using NanoString to assess effects on a range of genes. The tumor inflammation signature score (TIS) was also calculated.

Results:Preliminary Phase 1/2 biomarker data from paired tumor biopsies include the following: Immunohistochemistry for CD8 and PD-L1 (n=30) indicated robust and increased infiltration of CD8+ T cells and PD-L1 expression, both after combined treatment with RP1 and nivolumab and after single agent RP2 across different tumor types, and including reversal of T cell exclusion following prior combined treatment with ipilimumab and nivolumab in melanoma. Gene expression analysis (n=15) demonstrated a significant increase in the expression levels of genes associated with innate and adaptive immune activation and genes previously reported to be associated with responsiveness to anti-PD1 therapy, particularly CD8, CXCL9, CD27 and TIGIT, as well as consistently increased TIS.

Conclusion:Consistent with the pre-clinical data, preliminary clinical biomarker data indicate substantial increase in CD8 T cell infiltration and PD-L1 expression, as well as increased TIS score in the majority of patients treated with RP2 alone or RP1 and nivolumab combination. Particularly marked effects were seen in some patients with clinical responses which occurred independent of both baseline PD-L1 and prior anti-PD1 therapy status, which suggests potential broad utility of the RP1/2 treatment approach in igniting an anti-tumor immune response. Tumor mutation burden analysis and T cell receptor sequencing are currently underway and further updates of the dataset will be presented.

Citation Format: Kevin J. Harrington, Francesca Aroldi, Joseph J. Sacco, Mohammed M. Milhem, Brendan D. Curti, Ari M. Vanderwalde, Scott Baum, Adel Samson, Anna C. Pavlick, Jason A. Chesney, Jiaxin Niu, Terence D. Rhodes, Tawnya L. Bowles, Robert Conry, Anna Olsson-Brown, Douglas E. Laux, Pablo Nenclares, Lavita Menezes, Alex Deterding, Victoria Roulstone, Joan Kyula, Suzanne Thomas, Praveen K. Bommareddy, Selda Samakoglu, Andrea Pirzkall, Robert S. Coffin, Mark R. Middleton. Clinical biomarker studies with two fusion-enhanced versions of oncolytic HSV (RP1 and RP2) alone and in combination with nivolumab in cancer patients indicate potent immune activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB180.

422 An open-label, multicenter, phase 1/2 clinical trial of RP1, an enhanced potency oncolytic HSV, combined with nivolumab: updated results from the skin cancer cohorts

Background

RP1 is an enhanced potency oncolytic HSV encoding a fusogenic protein (GALV-GP R-) and GM-CSF which has previously demonstrated tolerable safety and tumor regression alone and with nivolumab in patients with a number of tumor types. Updated data from the phase 1 expansion with nivolumab, melanoma phase 2 (enrollment complete) and non-melanoma skin cancer (NMSC; enrollment ongoing) cohorts will be presented (NCT03767348). Enrollment of a further 125 patient anti-PD1 refractory cutaneous melanoma cohort; and activation of a cohort of anti-PD1 refractory NSCLC is underway.

Methods

Stage IIIb-IV melanoma patients for whom anti-PD-1 was indicated or who were refractory to prior anti-PD-1 alone or in combination with anti-CTLA-4, were enrolled. NMSC patients were anti-PD1 naïve. Patients received ≤8 doses of RP1 (≤10 mL/visit Q2W; first dose 106 PFU/mL then 107 PFU/mL) with nivolumab (240 mg IV Q2W for 4 months then 480 mg IV Q4W up to 2 years) from the second RP1 dose.

Results

As of 24th June 2020, 36 melanoma and 16 NMSC patients had been enrolled with follow up of <1–17 months. Of the melanoma patients, 16 previously anti-PD1 treated cutaneous (8 also prior anti-CTLA-4), 8 anti-PD1 naïve cutaneous, 6 mucosal, and 6 uveal. Of the NMSC patients, 10 had squamous cell (CSCC), 3 had a basal cell, 1 had Merkel cell carcinomas, and 2 had angiosarcoma. Treatment emergent adverse events (TEAEs) remain consistent with phase 1, with RP1 side effects generally of Grade 1/2 constitutional-type symptoms, with no exacerbation of the side effects expected for nivolumab. At the data cut-off, 5 previously anti-PD1 treated (4 also anti-CTLA-4) cutaneous melanoma patients, 4 anti-PD1 naïve cutaneous melanoma patients, two mucosal melanoma patients (one anti-PD1 refractory) and one uveal melanoma patient (ipi/nivo refractory) have achieved response (WHO criteria for uveal). For NMSC, for the 13 patients with >8 weeks follow up, one of two angiosarcoma patients and seven of eight CSCC patients (5 CR) have achieved response (CSCC ORR 87.5%; CR rate 62.5%, including of uninjected visceral disease). Tumor biopsies in patients continue to routinely show immune activation, including robust recruitment of CD8+ T cells, reversal of T cell exclusion, and increased PD-L1 expression. Treatment remains ongoing, and current data will be presented.

Conclusions

RP1 and nivolumab have continued to be well tolerated, with continued promising anti-tumor activity in patients with skin cancers, including those with anti-PD1 refractory and other difficult to treat melanomas, and in patients with CSCC.

An open-label, single-arm, phase II clinical trial of RP1, an enhanced potency oncolytic herpes virus, combined with nivolumab in four solid tumor types: Initial results from the skin cancer cohorts

e22050

Background: RP1 is an oncolytic HSV that encodes a fusogenic GALV-GP R- protein and GM-CSF. RP1 demonstrated tolerable safety and tumor regression alone and with nivolumab (nivo) in ph 1 in patients (pts) with a number of tumor types. To further define the efficacy of the combination, ph2 cohorts of 30 pts with 4 tumor types were then opened. Initial data from the melanoma (mel) and the non-mel skin cancer (NMSC) cohorts will be presented. Methods: Unresectable stage IIIb-IV mel pts for whom anti-PD-1 was indicated or who were refractory to 1 prior standard therapy including anti-PD-1 or ipi/nivo were enrolled. NMSC pts were anti-PD1 naïve. Pts received up to 8 doses of RP1 (<=10 mL/visit based on tumor diameter) Q2W (first dose 106 PFU/mL then 107 PFU/mL). From the second RP1 dose pts also received nivo (240 mg IV Q2W for 4 mos then 480 mg IV Q4W up to 2 yrs in the absence toxicity or confirmed progressive disease (PD)). Imaging was done every 8 wks and response assessed by RECISTv1.1 (with confirmation required for PD). Results: As of Jan 22nd 2020, 30 mel pts and 9 NMSC pts had been enrolled with follow up between <1 and 7mo. Of the mel pts 21 were cutaneous, 5 were mucosal and 4 were ocular. Of the NMSC pts, 6 had squamous cell, 1 had basal cell, 1 had Merkel cell carcinomas and 1 had angiosarcoma. Recruitment of the mel cohort is complete, with recruitment into the NMSC cohort ongoing. Based on initial data in melanoma, a further cohort of 125 pts with anti-PD1 refractory cutaneous mel has been opened. Adverse events (AEs) in the ph2 cohorts have been consistent with those in ph1, with RP1 side effects of in general Grade 1/2 constitutional and related symptoms, self-limiting within 72hrs of RP1 injections, with no exacerbation of the side effects expected for nivo. With currently short follow up, multiple objective responses have been observed in treatment naïve mel, anti-PD1 refractory mel (including ipi/nivo refractory and mucosal), and NMSC. Of note 3 of the first 4 anti-PD1 refractory mel pts treated are responding to treatment, as are 5 of the first 6 CSCC pts, including 3 CR. Tumor biopsies routinely showed immune activation, including robust recruitment of CD8+ T cells and increased PD-L1 expression. Treatment remains ongoing in the majority of patients, and current data will be presented. Conclusions: RP1 and nivo has continued to be well tolerated, with promising signs of efficacy in patients with skin cancers, including with anti-PD1 refractory disease. These data support the further development of RP1 combined with anti-PD1 blockade. Clinical trial information: NCT03767348 .

NuTide: 302—A phase Ib study of the ProTide NUC-3373 in combination with standard therapies in advanced colorectal cancer

TPS274

Background: Although 5-FU-based regimens such as FOLFOX and FOLFIRI remain the cornerstone of treatment for patients (pts) with colorectal cancer (CRC), their clinical utility is limited by resistance mechanisms and toxicity. Anti-cancer activity of 5-FU is dependent on conversion to an active metabolite, fluorodeoxyuridine-monophosphate (FUDR-MP), which binds to and inhibits thymidylate synthase (TS), a critical enzyme in de novo nucleotide synthesis and cell survival. However, due to multiple limitations including: reliance on enzymatic activation; catabolism by dihydropyrimidine dehydrogenase (DPD) and a short plasma half-life, 5-FU is not efficiently converted to FUDR-MP. NUC-3373, a phosphoramidate transformation of FUDR-MP, was designed to bypass the key resistance mechanisms that limit the clinical utility of 5-FU. NUC-3373 demonstrated a favorable PK/PD profile and promising efficacy signals in the first-in-human study (NuTide:301) in pts with advanced solid tumors. NUC-3373 has a longer plasma t1/2 (9.7 hours) than 5-FU (8-14 minutes) and generates high intracellular levels of FUDR-MP (Ghazaly et al ESMO, 2017). TS is efficiently inhibited and sequestered into TS-ternary complexes, depleting the pool of deoxythymidine monophosphate (dTMP) within 2-4 hours. Methods: NuTide:302 is a three-part, Phase Ib study in pts with advanced CRC who have relapsed after ≥2 prior lines of 5-FU-containing therapies. Primary objective is to identify a RP2D of NUC-3373 when administered weekly and q2w in combination with standard agents used in CRC treatment. Secondary objectives include safety, PK/PD and anti‐tumor activity. In Part 1, patients are receiving NUC-3373 with leucovorin (LV) to determine if LV augments TS inhibition. In Part 2, NUC-3373 (±LV) will be administered in dose escalating cohorts, in a modified 3+3 design, with either oxaliplatin (NUFOX) or irinotecan (NUFIRI). In Part 3, the NUFOX and NUFIRI regimens selected in Part 2 will be combined with biologics targeting VEGF or EGFR pathways. To date, 22 pts have received study treatment. Recruitment is ongoing in the US and Europe. Clinical trial information: NCT03428958.

Abstract C059: Inhibition of thymidylate synthase by the ProTide NUC-3373: in vitro analysis and clinical validation

Background: Although 5-FU-based regimens such as FOLFOX and FOLFIRI remain the standard of care for treatment of patients with colorectal cancer (CRC), their clinical utility is limited by resistance mechanisms and the production of toxic by-products. Anti-cancer activity of 5-FU requires its conversion to the active metabolite, fluorodeoxyuridine-monophosphate (FUDR-MP), which binds to and inhibits thymidylate synthase (TS), depleting dTMP, resulting in DNA damage. Due to breakdown by dihydropyrimidine dehydrogenase (DPD), a reliance on enzymatic activation and a short plasma half-life; 5-FU is a sub-optimal inhibitor of TS. NUC-3373, a phosphoramidate transformation of FUDR-MP, was designed to bypass the key resistance mechanisms associated with the activation and breakdown of 5-FU. Herein, we characterize the impact of DPD on NUC-3373 and the role of NUC-3373 on TS biology in vitro. The NuTide:302 clinical study (NCT03428958) is investigating NUC-3373 pharmacokinetics and dTMP levels. Methods: Sensitivity of nine CRC cell lines was assessed by sulforhodamine B assay and IC50values established, with two (one sensitive and one less sensitive) selected for further evaluation. Pharmacological inhibition by gimeracil was used to investigate DPD-induced catabolism in cells treated with 5-FU and NUC-3373. Thymidine supplementation was used to indirectly assess the effect of NUC-3373 on the de novopathway of dTMP synthesis. Immunocytochemistry and Western blot analysis were used to assess the localization and expression of TS. NuTide:302 is a three-part, Phase Ib study in patients with advanced CRC who have relapsed after ≥2 prior lines of 5-FU-containing therapies. Pharmacokinetic analyses via LC-MS from patient PBMCs are intended to determine whether leucovorin (LV) augments NUC-3373 inhibition of TS and its depletion of the dTMP pool. Results: Unlike 5-FU-treated cells, inhibition of DPD by gimeracil had no significant effect on survival following NUC-3373 treatment. Supplementation with exogenous thymidine rescued cells from NUC-3373-induced death. No correlation was found between pre-treatment TS protein expression and the IC50for NUC-3373. In selected cell lines treated with NUC-3373, TS ternary complexes were detected for at least 72 hours. Treatment with NUC-3373 was also associated with increased cytoplasmic TS expression. In the clinical setting, 22 patients have received NUC-3373 in NuTide:302. The clinical impact of LV on TS inhibition and dTMP pool depletion in patient samples will be presented. Conclusions: Unlike 5-FU, NUC-3373 was not catabolised by DPD, highlighting the ability of NUC-3373 to bypass a key rate-limiting factor associated with 5-FU. NUC-3373 targets the de novo pathway of dTMP synthesis and its cytotoxicity is not dependent on basal TS expression. Formation of long-lasting ternary complexes and increased cytoplasmic expression suggest that NUC-3373 is a potent inhibitor of TS activity. Data describing whether LV potentiates the impact of NUC-3373 on TS in patients will be presented.

Citation Format: Sarah P Blagden, Fiona G McKissock, Janet S Graham, Kristen K Ciombor, Francesca Aroldi, Lisa J Rodgers, Michelle Myers, Jordan Berlin, T.R. Jeffry Evans, David J Harrison. Inhibition of thymidylate synthase by the ProTide NUC-3373: in vitro analysis and clinical validation [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 C059. doi:10.1158/1535-7163.TARG-19-C059

An open label, multicenter, phase I/II study of RP1 as a single agent and in combination with PD1 blockade in patients with solid tumors

TPS2671

Background: RP1 is an attenuated oncolytic HSV-1 that expresses a fusogenic glycoprotein from gibbon ape leukemia virus (GALV-GP R-) and GM-CSF. RP1 induces potent GALV-GP R- enhanced immunogenic cell death and host anti-tumor immunity in murine tumor models and increases PD-L1 expression. This clinical trial (NCT03767348) was designed to test the hypotheses that RP1 is safe when given alone and together with nivolumab (phase 1) and has efficacy together with nivolumab in four tumor types (phase 2). Methods: The primary goals of this clinical trial in a total of ~150 patients are to define the safety profile of RP1 alone and together with nivolumab, determine the recommended phase 2 dose (phase 1), and then in four phase 2 cohorts, to determine objective response rate in patients with melanoma, non-melanoma skin cancer, urothelial carcinoma and MSI-H solid tumors. Secondary objectives include duration of response, CR rate, PFS, viral shedding, and immune biomarker analysis. Patients with advanced cancer who failed prior therapy were eligible for the phase I component. In Phase 2 patients with histologic diagnoses of the four tumor types (N=30 for each) and who meet safety criteria for nivolumab treatment are eligible. Prior treatment with checkpoint blockade is not allowed except for the melanoma cohort. In the phase 1 portion patients are treated by intra-patient dose escalation of virus (range, 104 - 108 PFU) by intratumoral injection every two weeks for 5 total doses followed by 12 patients dosed 8 times at the RP2D in combination with nivolumab. Phase 1 patients were divided into two groups based on presence of clinically accessible lesions amenable to direct injection or those with visceral/deep lesions requiring image guidance for injection. In the phase 2 portion patients will receive the RP2D for eight injections and nivolumab will be given starting with the second RP1 injection. For the phase 1 portion, a modified 3+3 dose escalation design is used to assess safety and in the phase 2 portion, statistical analysis will be performed using a two-stage three-outcome optimum design with objective responses determined by RECIST criteria. As of February 11, 2019, 27 patients have been enrolled. Clinical trial information: NCT03767348.

Palbociclib plus endocrine therapy in HER2 negative, hormonal receptor-positive, advanced breast cancer: A real-world experience

Data from 423 human epidermal growth factor receptor 2-negative (HER2-), hormone receptor-positive (HR+) advanced breast cancer (aBC) patients treated with palbociclib and endocrine therapy (ET) were provided by 35 Italian cancer centers and analyzed for treatment outcomes. Overall, 158 patients were treated in first line and 265 in second/later lines. We observed 19 complete responses and 112 partial responses. The overall response rate (ORR) was 31% (95% confidence interval [CI], 26.6-35.4) and clinical benefit was 52.7% (95% CI, 48-57.5). ORR was negatively affected by prior exposure to everolimus/exemestane ( p = 0.002) and favorably influenced by early line-treatment ( p < 0.0001). At 6 months, median progression-free survival was 12 months (95% CI, 8-16) and median overall survival was 24 months (95% CI, 17-30). More favorable outcomes were associated with palbociclib in early lines, no visceral metastases and no prior everolimus/exemestane. The main toxicity reported was neutropenia. Our results provide further support to the use of palbociclib with ET in HER2-, HR+ aBC. Differences in outcomes across patients subsets remain largely unexplained.

Metformin Use Is Associated With Longer Progression-Free Survival of Patients With Diabetes and Pancreatic Neuroendocrine Tumors Receiving Everolimus and/or Somatostatin Analogues

BACKGROUND & AIMS

Metformin seems to have anticancer effects. However, it is not clear whether use of glycemia and metformin affect outcomes of patients with advanced pancreatic neuroendocrine tumors (pNETs). We investigated the association between glycemia and progression-free survival (PFS) of patients with pNETs treated with everolimus and/or somatostatin analogues, as well as the association between metformin use and PFS time.

METHODS

We performed a retrospective analysis of 445 patients with advanced pNET treated at 24 medical centers in Italy from 1999 through 2015. Data on levels of glycemia were collected at time of diagnosis of pNET, before treatment initiation, and during treatment with everolimus (with or without somatostatin analogues), octreotide, or lanreotide. Diabetes was defined as prior or current use of glycemia control medication and/or fasting plasma glucose level ≥ 126 mg/dL, hemoglobin A1c ≥ 6.5% (48 mmol/L), or a random sample of plasma glucose ≥ 200 mg/dL (11.1 mmol/L), with reported classic symptoms of hyperglycemia or hyperglycemic crisis. Patients were assigned to groups based on diagnosis of diabetes before or during antitumor therapy. PFS was compared between patients with vs without diabetes. Among patients with diabetes, the association between metformin use and PFS was assessed. We performed sensitivity and landmark analyses to exclude patients who developed diabetes while receiving cancer treatment and to exclude a potential immortal time bias related to metformin intake.

RESULTS

PFS was significantly longer in patients with diabetes (median, 32.0 months) than without diabetes (median, 15.1 months) (hazard ratio for patients with vs without diabetes, 0.63; 95% confidence interval, 0.50-0.80; P = .0002). PFS of patients treated with metformin was significantly longer (median PFS, 44.2 months) than for patients without diabetes (hazard ratio for survival of patients with diabetes receiving metformin vs without diabetes, 0.45; 95% confidence interval, 0.32-0.62; P < .00001) and longer than for patients with diabetes receiving other treatments (median PFS, 20.8 months; hazard ratio, 0.49; 95% confidence interval, 0.34-0.69; P < .0001). In multivariable analysis, adjusted for other factors associated with outcomes, metformin was associated with longer PFS but level of glycemia was not. Metformin was associated with increased PFS of patients receiving somatostatin analogues and in those receiving everolimus, with or without somatostatin analogues. Sensitivity and landmark analyses produced similar results.

CONCLUSIONS

In a retrospective study of patients with pNETs, we found a significant association between metformin use and longer PFS.

Immunotherapy for pancreatic cancer: present and future

Despite the identification of some efficient drugs for the treatment of metastatic pancreatic cancer, this tumor remains one of the most lethal cancers and is characterized by a strong resistance to therapies. Pancreatic cancer has some unique features including the presence of a microenvironment filled with immunosuppressive mediators and a dense stroma, which is both a physical barrier to drug penetration and a dynamic entity involved in immune system control. Therefore, the immune system has been hypothesized to play an important role in pancreatic cancer. Thus, therapies acting on innate or adaptive immunity are being investigated. Here, we review the literature, report the most interesting results and hypothesize future treatment directions.

QT Prolongation and Anticancer Drugs: Is it a Cardiologist's Worry? The Oncologist's Point of View

Currently, many novel therapies are available for physicians treating cancer; some of them are associated with adverse cardiac events. One of the most worrisome cardiac event is QT prolongation, which is a risk factor for developing the potentially fatal torsade de pointe. Many classes of drugs, both anticancer and concomitant agents, are involved in this issue. We report a review of old and new commonly used agents with torsadogenic potential.

Abstract LB-256: Impact of metformin on progression-free survival in diabetic patients with advanced pancreatic neuroendocrine tumors (pNETs) receiving everolimus and/or somatostatin analogues: A sensitivity analysis of the PRIME-NET (pancreatic multicentric, retrospective, italian metformin) study

Introduction: Several studies have correlated the diabetic status with increased cancer risk and worse cancer prognosis, while metformin (MET) use is associated with a better prognosis. MET could display antitumor effects by modifying systemic metabolism, e.g. by decreasing of blood glucose, insulin and IGF1 levels, or by affecting cancer cell metabolism and proliferation, e.g. through AMPK activation and inhibition of protein/lipid synthesis. Preliminary findings of the PRIME-net retrospective study, conducted on 445 Italian pts, suggested that the addition of MET to EVE and/or SSAs provides clinical benefit in diabetic patient with advanced pancreatic NETs.

Methods: To exclude the possibility that the “time-on-treatment bias” could affect our results, with the risk that an early interruption of EVE or SSA-therapy due to early disease progression may result in lower pt exposure to these drugs and a consequently lower incidence of diabetes in poor responders, a sensitivity analysis on the PRIME-net study population was performed. The analysis considered only diabetics at baseline (BD), thus excluding pts who developed on-treatment diabetes as an adverse event (AE). All statistical tests were two-tailed and p-values&lt;0·05 were considered significant.

Results: Out of 445 pts, 237 were diabetics. Of them, 179 had baseline diabetes (BD) while 57 developed on-treatment diabetes as an adverse event. Among pts with BD, 80 (44.7%) received MET, while 99 (55.3%) were not treated with MET, but received other treatments including insulin. mPFS was 24.7 mo in pts with BD and 15.1 mo in normoglycemic ones (HR 0.70, 95%CI 0.55-0.91; p=0.007). In pts on MET therapy, mPFS was 43.7 mo (HR vs normoglycemic pts 0.52, 95%CI 0.36-0.76, p=0.0006), while it was 20.8 mo in pts not receiving MET (HR vs normoglycemic pts 0.87, 95%CI 0.65-1.17, p=0.37).

Conclusions: This sensitivity analysis confirms results emerged from the main analysis, thus demonstrating a mPFS advantage in diabetic patients with advanced pNETs patients receiving MET in combination with EVE and/or SSAs. Prospective investigations are ongoing to test the antitumor activity of MET in combination with everolimus and SSAs in normoglycaemic pts with advanced pNETs. Protocol number INT 85/15, approved by Ethical committee of fondazione IRCCS Istituto Tumori Milano on 15 June 2015.

Citation Format: Sara Pusceddu, Claudio Vernieri, Massimo Di Maio, Femia Daniela, Natalie Prinzi, Riccardo Marconcini, Francesca Spada, Sara Massironi, Alberto Bongiovanni, Maria Pia Brizzi, Davide Campana, Antongiulio Faggiano, Dario Giuffrida, Gianfranco Delle Fave, Sara Cingarlini, Francesca Aroldi, Lorenzo Antonuzzo, Rossana Berardi, Laura Catena, Roberto Buzzoni, Filippo de Braud. Impact of metformin on progression-free survival in diabetic patients with advanced pancreatic neuroendocrine tumors (pNETs) receiving everolimus and/or somatostatin analogues: A sensitivity analysis of the PRIME-NET (pancreatic multicentric, retrospective, italian metformin) study [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 LB-256. doi:10.1158/1538-7445.AM2017-LB-256

Multimodal imaging for clinical target volume definition in prone whole-breast irradiation: a single institution experience

Aim: The aim was identification of reference structures for breast clinical target volume (CTV) in prone position, throughout image fusion process. Materials & methods: We analyzed breast glandular tissue distribution in 20 diagnostic MRIs, referring to structures reported in ESTRO guidelines for supine irradiation. The volume containing breast glandular tissue in all cases was defined as MRI prone CTV (MRIpCTV). Then in ten subsequent patients planned for prone irradiation, MRI and computed tomography (CT) simulation was acquired. MRIpCTV was defined followed by our findings and transferred to CT for definitive delineation. Results: MRIpCTV was defined by the caudal edge of clavicular head, 3 mm above inframammary fold, by the medial thoracic artery, by a plane passing through the lateral surface of pectoralis muscles, by the anterior surface of pectoralis muscles and 3 mm from the skin. Deformed CTV was consistent with anatomy on CT; the limits chosen for MRIpCTV fit adequately also for CT. Conclusion: Prone irradiation is an alternative set up for selected cases, so the sample is very small. However, our suggestions could be of aid in defining prone CTV. The good consistency between MRI and CT seems to confirm that MRI may be unnecessary in routine practice.

Chemotherapy rechallenge after regorafenib treatment in metastatic colorectal cancer: still hope after the last hope?

INTRODUCTION

The introduction of biological agents in cancer therapy is changing the progression of metastatic colorectal cancer. Currently, resistance to biological agents is an emerging problem; the progression of the disease is caused by the development of resistant clones. According to some authors, these clones can be re-sensitized to traditional and previously utilized chemotherapy agents. The results of the CORRECT study demonstrated the efficacy of regorafenib monotherapy in both KRAS wild type and mutant pretreated patients (pts). Two recent reports showed the potential of reintroduction of chemotherapy, even after treatment with regorafenib.

PATIENTS AND METHODS

We performed a retrospective review of clinical data from patients treated with regorafenib at our institution between March 2012 and March 2013. We analysed patient characteristics, KRAS/NRAS status, response to treatment (evaluated by RECIST v1.1 criteria) and survival.

RESULTS

Regorafenib was administered to 128 patients, and 11 (8.6%) received post-regorafenib therapy (to our knowledge). Seven (63.6%) patients were wild type for KRAS/NRAS. Post-regorafenib therapy represented for all the patients at least the fourth line: all the pts received both oxaliplatin- and irinotecan-based chemotherapy, all of them were treated with bevacizumab, and 7 patients also received cetuximab. Eight patients (72.7%) were treated with standard chemotherapy after regorafenib (irinotecan monotherapy, capecitabine plus oxaliplatin or irinotecan, dacarbazine or raltitrexed), while 3 patients received an experimental therapy (clinical trial). Nine of the 11 (81.8%) patients had PD and 2 patients had SD. The median progression-free survival was 1.6+ months (range 0.5-3.5), the median OS post-regorafenib was 2.1+ months (range 0.5-10.2) and the 6-month OS was 27.3%.

CONCLUSION

Our retrospective analysis showed that after regorafenib therapy, re-introduction of chemotherapy is possible. Unfortunately, we reported a high percentage of disease progression beyond regorafenib, which is likely due to the high percentage of heavily pretreated patients (some received four or five types of therapy before regorafenib). We think that regorafenib could represent a chemotherapy resensitizing agent; however, additional studies are needed in patients who have received less pretreatment.

Pancreatic cancer: New hopes after first line treatment

Pancreatic cancer is the fourth leading cause of cancer-related death worldwide. Extensive research has yielded advances in first-line treatment strategies, but there is no standardized second-line therapy. In this review, we examine the literature trying to establish a possible therapeutic algorithm.

GEMOX: An Active Regimen for the Treatment of Luminal and Human Epidermal Growth Factor Receptor 2-Positive Metastatic Breast Cancer

BACKGROUND

Pretreated metastatic breast cancer (MBC) remains a formidable challenge with unmet needs both in terms of prolonged survival and quality-of-life-related issues.

METHODS

We collected data from 27 MBC patients treated with gemcitabine and oxaliplatin (GEMOX) at our institution between June 2009 and April 2015. The patients were heavily pretreated, and all had previously been exposed to anthracyclines and taxanes.

RESULTS

We achieved a complete response in 1 patient (4%), a partial response in 7 patients (26%) and stable disease in 12 patients (44%), while 6 patients (22%) experienced progressive disease. The response of 1 patient (4%) could not be evaluated because she interrupted her treatment during the first cycle due to a major reaction to oxaliplatin. We observed grade 4 hypertransaminasaemia in only 1 patient (4%) and grade 2 neuropathy in 16 patients (59%). Grade 3 leuconeutropenia was observed in 5 patients (18%). The median progression-free survival was 5.9 months and the median overall survival was 9.6 months.

CONCLUSIONS

GEMOX is an efficient and well-tolerated salvage regimen for MBC patients.

Gemcitabine Plus Nab-Paclitaxel as Second-Line and Beyond Treatment for Metastatic Pancreatic Cancer: a Single Institution Retrospective Analysis

Metastatic pancreatic cancer still represent one of the most deadly disease for which there are few therapeutic options, especially in second line and beyond setting. Nabpaclitaxel plus gemcitabine activity was demonstrated in first line setting, but there are no clear evidence suggesting its use after that. We report a retrospective data analysis of 23 patients who received nab-paclitaxel plus gemcitabine after first line treatment at our Oncology Department. We observed a significant clinical benefit (43,5%) with a median overall survival of 5 months. In addition, manageable side effects were reported. Our data, despite the small sample, seem to indicate that nab- paclitaxel plus gemcitabine is an active and well tolerated regimen even in pretreated patients.

[Ramucirumab-paclitaxel as second-line therapy for advanced gastric cancer: Poliambulanza experience]

We reported the cases of two patients affected by metastatic gastric cancer exposed to second line therapy with ramucirumab plus paclitaxel after progression. Both obtained a fast marker reduction with a very favourable toxicity profile. In the first case, a woman affected by peritoneal carcinomatosis, the disease had been stable for 8 months despite of the chemotherapy suspension after 3 cycles; whereas in the second case, a highly symptomatic man with a heavy tumor load (gastric tumor and multiple bone, node and peritoneal metastases) obtained an immediate clinical benefit even if of relatively short duration with a good tolerability.

[Efficacy and safety of antivascular drugs after anti-EFGR: aflibercept after cetuximab, a clinical case]

We describe a case of a man affected by colon adenocarcinoma with metachronous nodes and liver metastases (resected), exposed to first line therapy with FOLFOX-cetuximab. After disease progression, a second line based on FOLFIRI-aflibercept was started achieving an initial partial response followed by a long-lasting disease stability with a good tolerability.

Pancreatic Cancer: Promises and Failures of Target Therapies

Currently, few efficient therapies are available to battle pancreatic cancer. Mechanisms underlying this cancer are not well known and researchers are trying to identify new therapeutic targets. Here, we present a review of new treatments and their results in recent years.

Oxaliplatin-induced hypersensitivity reaction: underlying mechanisms and management

Hypersensitivity reactions are rare but feared drugs adverse effect. These reactions are not uncommon with anticancer drugs, such as taxanes, monoclonal antibodies, and platinum compounds. Oxaliplatinum, a third-generation platinum compound, one of the mainstay drugs in the treatment of many gastrointestinal cancers, can give rise to hypersensitivity reactions, sometimes with fatal outcomes. In this paper, we reviewed the incidence and mechanisms underlying the occurrence of this event, highlighting the most recent advances concerning the pathogenesis of the reaction and also reporting possible risk factors identified and the most effective treatment in preventing the onset of this event.

Tyrosine Kinase Inhibitors in EGFR-Mutated Large-Cell Neuroendocrine Carcinoma of the Lung? A Case Report

Large-cell neuroendocrine carcinoma (LCNEC) of the lung is a high-grade carcinoma belonging to the neuroendocrine tumors of the lung and is different from typical lung large-cell carcinoma. It represents about 3% of all pulmonary malignancies and is characterized by neuroendocrine cytologic features. The treatment usually is platinum-based chemotherapy, however the outcome remains poor. Therefore new therapeutic options are needed. Tyrosine kinase inhibitors have demonstrated greater efficacy and better tolerability than standard chemotherapy in non-small-cell lung cancer harboring epidermal growth factor receptor (EGFR) mutations. EGFR gene mutations were also rarely identified in LCNEC. We report a patient with lung LCNEC activating EGFR mutations who showed an impressive response to gefitinib.

Blind Snipers: Relevant Off Target Effects of Non-chemotherapeutic Agents in Oncology: Review of the Literature

In recent years an increasing attention is focused on the potential effects of drugs on cancer incidence and/or cancer survival. Many medications of common use, developed for a variety of medical non-cancer situations, have been found to have potential anti- cancer effects. In this article, we performed an overview of the literature evidence for several commonly used non-cancer medications, such as aspirin, beta-blockers, metformin and other anti- diabetics, cardiac glycosides, anticoagulant heparin, statins, psychotropic drugs, vitamins, calcium and estrogens which have been shown to have anticancer effects, in observational and experimental studies. A huge amount of data supports the idea that a few of these commonly used medicines could decrease cancer death-rate, particularly aspirin, statins and metformin, crosswise different types of cancer. To date, no mature data are available from randomized and prospective trials; perhaps, the results of some studies underway will allow us to answer some questions on the possible use of these drugs in our clinical practice in primary and secondary prevention, or even in adjuvant setting.