Recent advancement in targeted therapy and role of emerging technologies to treat cancer

Cancer is a complex disease that causes abnormal cell growth and spread. DNA mutations, chemical or environmental exposure, viral infections, chronic inflammation, hormone abnormalities, etc., are underlying factors that can cause cancer. Drug resistance and toxicity complicate cancer treatment. Additionally, the variability of cancer makes it difficult to establish universal treatment guidelines. Next-generation sequencing has made genetic testing inexpensive. This uncovers genetic mutations that can be treated with specialty drugs. AI (artificial intelligence), machine learning, biopsy, next-generation sequencing, and digital pathology provide personalized cancer treatment. This allows for patient-specific biological targets and cancer treatment. Monoclonal antibodies, CAR-T, and cancer vaccines are promising cancer treatments. Recent trial data incorporating these therapies have shown superiority in clinical outcomes and drug tolerability over conventional chemotherapies. Combinations of these therapies with new technology can change cancer treatment and help many. This review discusses the development and challenges of targeted therapies like monoclonal antibodies (mAbs), bispecific antibodies (BsAbs), bispecific T cell engagers (BiTEs), dual variable domain (DVD) antibodies, CAR-T therapy, cancer vaccines, oncolytic viruses, lipid nanoparticle-based mRNA cancer vaccines, and their clinical outcomes in various cancers. We will also study how artificial intelligence and machine learning help find new cancer treatment targets.

Use of Talimogene Laherparepvec to Treat Cutaneous Squamous Cell Carcinoma in a Renal Transplant Patient

A 66-year-old female with a history of two renal transplants due to recurrent thrombotic thrombocytopenic purpura presented to clinic with multiple lesions identified to be non-metastatic cutaneous squamous cell carcinoma (CSCC). The patient previously underwent multiple Mohs procedures and radiation therapy treatment but continued to develop CSCC lesions with increasing frequency. After discussing multiple treatment options, it was elected to pursue treatment with Talimogene laherparepvec (T-VEC) given the systemic immune responses it can cause, with low theoretical risk of graft rejection. After starting intratumoral T-VEC injections, treated lesions began to decrease in size, and a reduction in the rate of new CSCC lesions was observed. Treatment was held due to unrelated renal complications during which time new CSCCs developed. Patient was restarted on T-VEC therapy with no recurrent renal issues. Upon reinitiating treatment, injected and non-injected lesions showed reduction in size, and the development of new lesions again ceased. One injected lesion was resected via Mohs micrographic surgery due to its size and discomfort. On sectioning, this demonstrated an exuberant lymphocytic perivascular infiltrate which was consistent with treatment response to T-VEC, with little active tumor. With high rates of non-melanoma skin cancer in renal transplant patients, their transplant status significantly limits treatment options, specifically with regards to anti-PD-1 therapy. This case suggests T-VEC can generate local and systemic immune responses in the setting of immunosuppression and that T-VEC may be a beneficial therapeutic option for transplant patients with CSCC.

Neoadjuvant nivolumab + T-VEC combination therapy for resectable early stage or metastatic (IIIB-IVM1a) melanoma with injectable disease: study protocol of the NIVEC trial

Background

Trials investigating neoadjuvant treatment with immune checkpoint inhibitors (ICI) in patients with melanoma have shown high clinical and pathologic response rates. Treatment with talimogene laherparepvec (T-VEC), a modified herpes simplex virus type-1 (HSV-1), is approved for patients with unresectable stage IIIB-IVM1a melanoma and has the potential to make tumors more susceptible for ICI. Combination ICI and intralesional T-VEC has already been investigated in patients with unresectable stage IIIB-IV disease, however, no data is available yet on the potential benefit of this combination therapy in neoadjuvant setting.

Methods

This single center, single arm, phase II study aims to show an improved major pathologic complete response (pCR) rate, either pCR or near-pCR, up to 45% in 24 patients with resectable stage IIIB-IVM1a melanoma upon neoadjuvant combination treatment with intralesional T-VEC and systemic nivolumab (anti-PD-1 antibody). Patients will receive four courses of T-VEC up to 4 mL (first dose as seroconversion dose) and three doses of nivolumab (240 mg flatdose) every 2 weeks, followed by surgical resection in week nine. The primary endpoint of this trial is pathologic response rate. Secondary endpoints are safety, the rate of delay of surgery and event-free survival. Additionally, prognostic and predictive biomarker research and health-related quality of life evaluation will be performed.

Discussion

Intralesional T-VEC has the capacity to heighten the immune response and to elicit an abscopal effect in melanoma in combination with ICI. However, the potential clinical benefit of T-VEC plus ICI in the neoadjuvant setting remains unknown. This is the first trial investigating the efficacy and safety of neoadjuvant treatment of T-VEC and nivolumab followed by surgical resection in patients with stage IIIB-IVM1a melanoma, with the potential of high pathologic response rates and acceptable toxicity.

Trial registration

This trial was registered in the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT- number: 2019–001911-22) and the Central Committee on Research Involving Human Subjects (NL71866.000.19) on 4th June 2020.

Secondary identifying number: NCT04330430.

Unraveling the Effects of a Talimogene Laherparepvec (T-VEC)-Induced Tumor Oncolysate on Myeloid Dendritic Cells

T-VEC, a HSV-1 derived oncolytic virus, is approved for the treatment of advanced melanoma. The mechanisms that underly the systemic anti-tumor effect that is seen following intratumoral injection have not yet been studied but are likely to be mediated by myeloid dendritic cells (myDC) that initiate an adaptive immune response. In this study we could demonstrate that T-VEC is non-toxic for human myDC. T-VEC and a T-VEC oncolysate of melanoma cell lines were able to mature human myDC. myDC were able to take up lysed melanoma cells and cross-present melanoma-derived tumor antigens to antigen-specific T cells. Our results support the possible role of myDC as mediators of an adaptive anti-tumor effect and intratumoral co-administration of T-VEC plus autologous myDC could be a complementary treatment option. A clinical trial that investigates this hypothesis is currently ongoing.

Talimogene Laherparepvec in Non-Melanoma Cancers

BACKGROUND

Talimogene laherparepvec (T-VEC) is the first oncolytic virus therapy approved by the United States Food and Drug Administration (in 2015) for the treatment of advanced-stage melanoma. Despite a paucity of Phase III trials for T-VEC as a therapy for non-melanoma cancers, successful off-label use of T-VEC for this purpose has been reported in the literature.

OBJECTIVE

We sought to review the literature describing T-VEC as a treatment for non-melanoma cancer.

METHODS

Systematic searches of the PubMed literature database and ClinicalTrials.gov website were performed in July 2020, focusing on T-VEC in combination with non-melanoma cancer, including squamous cell carcinoma, Merkel cell carcinoma, sarcoma, cutaneous B-cell lymphoma, and cutaneous T-cell lymphoma. Articles were screened based on their title and abstract.

RESULTS

Nine articles with 87 patients were included. Relevant articles included case reports, case series, and Phase I and Phase II trials. The majority of patients in the studies had refractory cancers or had been heavily pretreated. Overall, T-VEC demonstrated efficacy for non-melanoma cancer, both independently and in combination with biologics.

CONCLUSION

T-VEC has demonstrated efficacy for non-melanoma cancers. Phase III trials of T-VEC for this indication are warranted to expand its clinical utility.

Is there still a role for talimogene laherparepvec (T-VEC) in advanced melanoma? An indirect efficacy comparison of T-VEC plus ipilimumab combination therapy versus T-VEC alone as salvage therapy in unresectable metastatic melanoma

BACKGROUND

Talimogene laherparepvec (T-VEC) improves overall survival (OS) in unresectable stage IIIB/C-IV melanoma T-VEC may have synergistic effects with CTLA-4 inhibitors In the absence of a trial comparing T-VEC and ipilimumab (T-VEC + IPI) to T-VEC, we applied a novel indirect comparison method using extrapolated OS curves to estimate OS outcomes in a simulated trial comparing both regimens in stage IIIB/C-IV unresectable melanoma.

RESEARCH DESIGN AND METHODS

Two trials with extractable OS curves for a T-VEC versus T-VEC + IPI comparison were identified. Outcomes were adjusted for heterogeneity in prognostic factors using a calculated adjustment factor. T-VEC and adjusted/unadjusted T-VEC+IPI curves were plotted with 95% CIs.

RESULTS

Unadjusted indirect OS comparison of T-VEC versus T-VEC + IPI revealed no significant difference up to 15 months. Extrapolation beyond 15 months showed significant survival benefits for T-VEC + IPI over T-VEC, confirmed in adjusted analyses. The expected OS percentage at 48 months is 32.0% (95% CI = 26.6-37.3) for T-VEC, 60.0% (95% CI = 46.2-69.1) for unadjusted, and 81.1% (95% CI = 72.3-85.9) for adjusted T-VEC + IPI.

CONCLUSIONS

Our novel indirect comparison suggests that T-VEC + IPI may demonstrate a significantly improved OS versus T-VEC alone. Findings may portend a possible role for the addition of T-VEC to advanced melanoma treatment regimens in select patients as salvage therapy.

T-VEC for stage IIIB-IVM1a melanoma achieves high rates of complete and durable responses and is associated with tumor load: a clinical prediction model

BACKGROUND

Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex type 1 virus and known as an effective oncolytic immunotherapy for injectable cutaneous, subcutaneous and nodal melanoma lesions in stage IIIB-IVM1a patients. This study set out to identify prognostic factors for achieving a complete response that can be used to optimize patient selection for T-VEC monotherapy.

METHODS

Patients with stage IIIB-IVM1a melanoma, treated with T-VEC at the Netherlands Cancer Institute between 2016-12 and 2020-01 with a follow-up time > 6 months, were included. Data were collected on baseline characteristics, responses and adverse events (AEs). Uni- and multivariable analyses were conducted, and a prediction model was developed to identify prognostic factors associated with CR.

RESULTS

A total of 93 patients were included with a median age of 69 years, median follow-up time was 16.6 months. As best response, 58 patients (62%) had a CR, and the overall response rate was 79%. The durable response rate (objective response lasting > 6 months) was 51%. Grade 1-2 AEs occurred in almost every patient. Tumor size, type of metastases, prior treatment with systemic therapy and stage (8Th AJCC) were independent prognostic factors for achieving CR. The prediction model includes the predictors tumor size, type of metastases and number of lesions.

CONCLUSIONS

This study shows that intralesional T-VEC monotherapy is able to achieve high complete and durable responses. The prediction model shows that use of T-VEC in patients with less tumor burden is associated with better outcomes, suggesting use earlier in the course of the disease.

Injectables in Head and Neck Cutaneous Melanoma Treatment

Head and neck cutaneous melanomas pose many treatment challenges. Intratumoral injectables offer local and possibly systemic therapy in unresectable lesions. Talimogene laherparepvec, an injectable oncolytic type 1 herpes simplex virus, can improve durable response rates compared with systemic granulocyte-macrophage colony-stimulating factor therapy in patients with stage IIIB to IVM1a unresectable melanoma. These benefits were most noticed in lower-stage subsets and treatment naive patients. Efficacy of talimogene laherparepvec was maintained in patients with head and neck melanoma. Talimogene laherparepvec plus systemic immunotherapies is being studied, with promising preliminary data. Numerous ongoing clinical trials are investigating other viral and nonviral injectables.

A Retrospective Chart Review Study of Real-World Use of Talimogene Laherparepvec in Unresectable Stage IIIB-IVM1a Melanoma in Four European Countries

Introduction

Talimogene laherparepvec (T-VEC; IMLYGIC^®, Amgen Inc.) is an oncolytic immunotherapy approved in Europe for the treatment of unresectable metastatic melanoma (stage IIIB–IVM1a). This study characterised real-world use of T-VEC in four European countries.

Methods

Data on demographics, treatment pattern, safety, and clinical effectiveness were examined in a retrospective chart review of patients with stage IIIB–IVM1a unresectable melanoma treated with T-VEC in surgical (the Netherlands) and medical (Austria, Germany, UK) oncology settings.

Results

Overall, 66 patients were included (the Netherlands: n = 31; Austria, Germany, UK: n = 35). The median age was 69 years and 59.1% were female. At the time of T-VEC initiation, 47 patients (71.2%) had stage IIIB/C disease; of these, 30 were from the Netherlands. Although 72.7% patients overall received T-VEC as first-line therapy, this was higher in the Netherlands than the other countries (93.5% vs 54.3%). Of the 47 patients who discontinued T-VEC, 26 (55.3%) had no remaining injectable lesions (potentially indicating complete response); 20/26 of these patients were from the Netherlands. One patient discontinued T-VEC due to toxicity.

Conclusion

This study is the first comprehensive multinational evaluation of the use of T-VEC to treat unresectable stage IIIB/C–IVM1a melanoma in real-world clinical practice in Europe. The differences between European countries were apparent, with physicians in the Netherlands using T-VEC in patients with earlier advanced disease stage and in the first-line setting compared with other countries.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-020-01590-w.

Complete response with talimogene laherparepvec in recurrent melanoma of the ear: A case report

The current standard of care for cutaneous melanoma of the ear is surgical excision. This approach may result in unfavorable functional and cosmetic outcomes. We report here a case of recurrent melanoma of the ear that achieved complete response with talimogene laherparepvec treatment after the patient declined surgical resection.

Talimogene laherparepvec treatment to overcome loco-regional acquired resistance to immune checkpoint blockade in tumor stage IIIB-IV M1c melanoma patients

BACKGROUND

Resistance to immune checkpoint blockade and targeted therapy in melanoma patients is currently one of the major clinical challenges. With the approval of talimogene laherparepvec (T-VEC), oncolytic viruses are now in clinical practice for locally advanced or non-resectable melanoma. Here, we describe the usage of T-VEC in stage IVM1b-M1c melanoma patients, who achieved complete remission or stable disease upon systemic treatment but suffered from a loco-regional recurrence. To our knowledge, there are no case reports so far describing T-VEC as a means to overcome acquired resistance to immune checkpoint blockade or targeted therapy.

METHODS

All melanoma patients in our department treated with T-VEC in the period of 2016-2018 were evaluated retrospectively. Data on clinicopathological characteristics, treatment response, and toxicity were analyzed.

RESULTS

Fourteen melanoma patients were treated with T-VEC in our center. Six patients (43%) received T-VEC first-line. In eight patients (57%), T-VEC followed a prior systemic therapy. Three patients with M1b stage and one patient with M1c stage melanoma were treated with T-VEC. These patients suffered from loco-regional progress, whilst distant metastases had regressed during prior systemic treatment. 64% of patients showed a benefit from therapy with T-VEC. The durable response rate was 36%.

CONCLUSION

T-VEC represents an effective and tolerable treatment option. This is true not only for loco-regionally advanced melanoma patients, but also for patients with stable or regressive systemic metastases who develop loco-regionally acquired resistance upon treatment with immune checkpoint blockade or targeted therapy. A sensible selection of suitable patients seems to be crucial.

Oncolytic Viruses for the Treatment of Metastatic Melanoma

OPINION STATEMENT

There is an unmet need for additional treatments for metastatic melanoma, besides anti-PD1 antibodies which are FDA approved for adjuvant therapy for stage III or resected stage IV melanoma. Talimogene laherparepvec (T-VEC) is the first and only FDA-approved oncolytic virus for the treatment of melanoma. New viral vectors including coxsackieviruses, HF-10, adenovirus, reovirus, echovirus, and newcastle disease virus are currently under active development and investigation with varying degrees of efficacy in targeting melanoma. The use of T-VEC as a neoadjuvant therapy is emerging, but more data is needed at this point. T-VEC has also shown promise for use in combination therapy with ipilimumab, as T-VEC plus ipilimumab has a significantly higher objective response compared to ipilimumab alone. Data comparing T-VEC in combination with PD-1 checkpoint inhibitors is awaited, and a phase III trial is underway. It is likely that oncolytic viruses will have long-term application in the treatment of melanoma and that T-VEC in particular will continue to have a role in the treatment of patients with readily accessible cutaneous lesions both for local control and synergistic induction of antitumor immunity as part of combination therapies.

Intratumoral Immunotherapy-Update 2019

Intratumoral immunotherapies aim to trigger local and systemic immunologic responses via direct injection of immunostimulatory agents with the goal of tumor cell lysis, followed by release of tumor‐derived antigens and subsequent activation of tumor‐specific effector T cells. In 2019, a multitude of intratumoral immunotherapies with varied mechanisms of action, including nononcolytic viral therapies such as PV‐10 and toll‐like receptor 9 agonists and oncolytic viral therapies such as CAVATAK, Pexa‐Vec, and HF10, have been extensively evaluated in clinical trials and demonstrated promising antitumor activity with tolerable toxicities in melanoma and other solid tumor types. Talimogene laherparepvec (T‐VEC), a genetically modified herpes simplex virus type 1–based oncolytic immunotherapy, is the first oncolytic virus approved by the U.S. Food and Drug Administration for the treatment of unresectable melanoma recurrent after initial surgery. In patients with unresectable metastatic melanoma, T‐VEC demonstrated a superior durable response rate (continuous complete response or partial response lasting ≥6 months) over subcutaneous GM‐CSF (16.3% vs. 2.1%; p < .001). Responses were seen in both injected and uninjected lesions including visceral lesions, suggesting a systemic antitumor response. When combined with immune checkpoint inhibitors, T‐VEC significantly improved response rates compared with single agent; similar results were seen with combinations of checkpoint inhibitors and other intratumoral therapies such as CAVATAK, HF10, and TLR9 agonists. In this review, we highlight recent results from clinical trials of key intratumoral immunotherapies that are being evaluated in the clinic, with a focus on T‐VEC in the treatment of advanced melanoma as a model for future solid tumor indications.

Implications for Practice

This review provides oncologists with the latest information on the development of key intratumoral immunotherapies, particularly oncolytic viruses. Currently, T‐VEC is the only U.S. Food and Drug Administration (FDA)‐approved oncolytic immunotherapy. This article highlights the efficacy and safety data from clinical trials of T‐VEC both as monotherapy and in combination with immune checkpoint inhibitors. This review summarizes current knowledge on intratumoral therapies, a novel modality with increased utility in cancer treatment, and T‐VEC, the only U.S. FDA‐approved oncolytic viral therapy, for medical oncologists. This review evaluates approaches to incorporate T‐VEC into daily practice to offer the possibility of response in selected melanoma patients with manageable adverse events as compared with other available immunotherapies.

This review highlights recent results from clinical trials of key intratumoral immunotherapies that are being evaluated in the clinic, with a focus on talimogene laherparepvec in the treatment of advanced melanoma as a model for future solid tumor indications.

Biodistribution, shedding, and transmissibility of the oncolytic virus talimogene laherparepvec in patients with melanoma

Background

Talimogene laherparepvec (T-VEC) is an intralesionally delivered, modified herpes simplex virus type-1 oncolytic immunotherapy. The biodistribution, shedding, and potential transmission of T-VEC was systematically evaluated during and after completion of therapy in adults with advanced melanoma.

Methods

In this phase 2, single-arm, open-label study, T-VEC was administered into injectable lesions initially at 10⁶ plaque-forming units (PFU)/mL, 10⁸ PFU/mL 21 days later, and 10⁸ PFU/mL every 14 (±3) days thereafter. Injected lesions were covered with occlusive dressings for ≥1 week. Blood, urine, and swabs from exterior of occlusive dressings, surface of injected lesions, oral mucosa, anogenital area, and suspected herpetic lesions were collected throughout the study. Detectable T-VEC DNA was determined for each sample type; infectivity was determined for all swabs with detectable T-VEC DNA.

Findings

Sixty patients received ≥1 dose of T-VEC. During cycles 1–4, T-VEC DNA was detected in blood (98·3% of patients, 36·7% of samples), urine (31·7% of patients, 3·0% of samples) and swabs from injected lesions (100% of patients, 57·6% of samples), exterior of dressings (80% of patients,19·5% of samples), oral mucosa (8·3% of patients, 2·5% of samples), and anogenital area (8·0% of patients, 1·1% of samples). During the safety follow-up period, T-VEC DNA was only detected on swabs from injected lesions (14% of patients, 5.8% of samples). T-VEC DNA was detected in 4/37 swabs (3/19 patients) of suspected herpetic lesions. Among all samples, only those from the surface of injected lesions tested positive for infectivity (8/740 [1·1%]). Three close contacts reported signs and symptoms of suspected herpetic origin; however, no lesions had detectable T-VEC DNA.

Interpretation

Using current guidelines, T-VEC can be administered safely to patients with advanced melanoma and is unlikely to be transmitted to close contacts with appropriate use of occlusive dressings.

Fund

This study was funded by Amgen Inc.: ClinicalTrials.gov, NCT02014441.

Final analyses of OPTiM: a randomized phase III trial of talimogene laherparepvec versus granulocyte-macrophage colony-stimulating factor in unresectable stage III-IV melanoma

Background

Talimogene laherparepvec is an oncolytic immunotherapy approved in the US, Europe, Australia and Switzerland. We report the final planned analysis of OPTiM, a randomized open-label phase III trial in patients with unresectable stage IIIB–IVM1c melanoma.

Methods

Patients were randomized 2:1 to receive intratumoral talimogene laherparepvec or subcutaneous recombinant GM-CSF. In addition to overall survival (OS), durable response rate (DRR), objective response rate (ORR), complete responses (CR), and safety are also reported. All final analyses are considered to be descriptive and treatment responses were assessed by the investigators.

Results

Of 436 patients in the intent-to-treat population, 295 were allocated to talimogene laherparepvec and 141 to GM-CSF. Median follow-up in the final OS analysis was 49 months. Median OS was 23.3 months (95% confidence interval [CI], 19.5–29.6) and 18.9 months (95% CI, 16.0–23.7) in the talimogene laherparepvec and GM-CSF arms, respectively (unstratified hazard ratio, 0.79; 95% CI, 0.62–1.00; p = 0.0494 [descriptive]). DRR was 19.0 and 1.4% (unadjusted odds ratio, 16.6; 95% CI, 4.0–69.2; p < 0.0001); ORR was 31.5 and 6.4%. Fifty (16.9%) and 1 (0.7%) patient in the talimogene laherparepvec and GM-CSF arms, respectively, achieved CR. In talimogene laherparepvec-treated patients, median time to CR was 8.6 months; median CR duration was not reached. Among patients with a CR, 88.5% were estimated to survive at a 5-year landmark analysis. Talimogene laherparepvec efficacy was more pronounced in stage IIIB–IVM1a melanoma as already described in the primary analysis. The safety reporting was consistent with the primary OPTiM analysis.

Conclusions

In this final planned OPTiM analysis, talimogene laherparepvec continued to result in improved longer-term efficacy versus GM-CSF and remained well tolerated. The final analysis also confirms that talimogene laherparepvec was associated with durable CRs that were associated with prolonged survival.

Trial registration

ClinicalTrials.gov identifier: NCT00769704.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0623-z) contains supplementary material, which is available to authorized users.

Beyond PD-1 Immunotherapy in Malignant Melanoma

For many years, the standard therapy for malignant melanoma was based mainly on surgical resection. Unfortunately, this treatment is curative only in the early localized stage of this malignancy. The metastatic stage of malignant melanoma still remains a huge therapeutic challenge. Despite the many new therapeutic options that have become available over the last years, there is a constant need for safer and more effective treatment modalities. There has been a dynamic development of various anti-cancer immunotherapies directed against new molecular targets. A number of clinical trials are currently being conducted to confirm their effectiveness and safety. In this review of the literature, we summarize the contemporary knowledge on promising new immunotherapies beyond the currently available treatment options for malignant melanoma, including oncolytic immunotherapy, selective inhibitors of indoleamine 2,3-dioxygenease, anti-PD-(L)1 (programmed death ligand 1) drugs, immune checkpoint protein LAG-3 antibodies, inhibitors of histone deacetylase (HDAC) and inhibitors of B7-H3.

Real-World Use of Talimogene Laherparepvec in German Patients with Stage IIIB to IVM1a Melanoma: A Retrospective Chart Review and Physician Survey

Introduction

Talimogene laherparepvec is a first-in-class oncolytic immunotherapy for intratumoral injection with proven efficacy and tolerability in patients with unresectable early metastatic melanoma (stage IIIB–IVM1a) in the pivotal phase III OPTiM study. The objective was to characterize melanoma patients treated with talimogene laherparepvec in routine clinical practice in Germany.

Methods

A retrospective chart review was conducted in unresectable stage IIIB–IVM1a melanoma patients. Data on demographics, disease and medical history, and use of talimogene laherparepvec were collected. A survey was also conducted to understand physician treatment decisions.

Results

Data for 27 patients who initiated talimogene laherparepvec between June 2016 and July 2017 were analyzed (median age 68; stage IIIB/C disease 56%). All patients had prior surgery, and over half had repeated resections for recurrent disease (median 3). Overall, 48% of patients received at least one prior local treatment, mainly radiation therapy or electrochemotherapy. Talimogene laherparepvec was first-line systemic therapy in 63% of patients. The most frequent prior systemic treatment was immunotherapy (7/27 patients). At end of follow-up, 13 patients were still on talimogene laherparepvec and 14 patients had discontinued treatment. Among those who discontinued, 8 (57%) did not receive subsequent systemic therapy. Only one patient receiving first-line talimogene laherparepvec received a subsequent systemic therapy. Three patients stopped treatment because of no remaining injectable lesions. Median treatment duration was 22.1 weeks overall and 27.9 weeks in stage IIIB/C disease patients. Nearly all cutaneous lesions (93%) were injected with talimogene laherparepvec compared to subcutaneous (83%) and nodal lesions (77%). No new safety signals were reported. The main reasons given in the physician survey for treating with talimogene laherparepvec were good tolerability, overall efficacy, and lack of contraindications.

Conclusion

Talimogene laherparepvec is now included as a routine treatment option for unresectable early metastatic melanoma in Germany. This study characterizes the first patients treated with talimogene laherparepvec in Europe and confirms the good tolerability observed in clinical trials.

Trial Registration

EUPAS registry, EUPAS17410.

Funding

Amgen Inc.

Electronic supplementary material

The online version of this article (10.1007/s12325-018-0850-6) contains supplementary material, which is available to authorized users.

The Oncolytic Herpes Simplex Virus Talimogene Laherparepvec Shows Promising Efficacy in Neuroendocrine Cancer Cell Lines

Metastatic neuroendocrine cancer still constitutes a palliative situation, lacking promising treatment options. Oncolytic virotherapy, a novel type of virus-based immunotherapy, lyses tumor cells using genetically engineered viruses thereby activating the immune system to induce an optimized antitumor response which could bring down tumor masses to a stage of minimal residual tumor disease. The oncolytic vector talimogene laherparepvec (T-VEC, herpes simplex virus [HSV] type 1) has already shown excellent safety profiles in clinical studies and has become the first ever FDA/EMA-approved oncolytic virus (OV). This work presents a first preclinical assessment of this state-of-the-art OV, using a panel of human neuroendocrine tumor/neuroendocrine carcinoma (NET/NEC) cell lines. Cytotoxicity, transgene expression, and viral replication patterns were studied. Furthermore, the antiproliferative activity was compared to the one of mTOR inhibitor Everolimus and also interactions between the OV and Everolimus were evaluated. Moreover, virostatic effects of ganciclovir (GCV) on replication of T-VEC were assessed and electron microscopic pictures were taken to comprehend viral envelopment and details of the replication cycle of T-VEC in human neuroendocrine cancer. It could be shown that T-VEC infects, replicates in, and lyses human NET/NEC cells exhibiting high oncolytic efficiencies already at quite low virus concentrations. Interestingly, Everolimus was not found to have any relevant impact on rates of viral replication, but no additive effects could be proved using a combinatorial therapy regimen. On the other hand, GCV was shown to be able to limit replication of T-VEC, thus establishing an important safety feature for future treatments of NET/NEC patients. Taken together, T-VEC opens up a promising novel treatment option for NET/NEC patients, warranting its further preclinical and clinical development.

Kaposi's varicelliform eruption in a patient with metastatic melanoma and primary cutaneous anaplastic large cell lymphoma treated with talimogene laherparepvec and nivolumab

Background

Immune-directed therapies have become front-line therapy for melanoma and are transforming the management of advanced disease. In refractory cases, multi-modal immunoncology (IO) approaches are being utilized, including combining immune checkpoint blockade (ICB) with oncolytic herpes viruses. Talimogene laherparepvec (T-VEC) is the first genetically modified oncolytic viral therapy (OVT) approved for the treatment of recurrent and unresectable melanoma. The use of IO in patients with concomitant malignancies and/or compromised immune systems is limited due to systematic exclusion from clinical trials. For example, a single case report of a solid organ transplant patient successfully treated with T-VEC for metastatic melanoma has been reported. Furthermore, the use of ICB in T-cell malignancies is limited and paradoxical worsening has been described. To our knowledge, this is the first report of dual ICB/T-VEC being administered to a patient with concurrent primary cutaneous anaplastic large cell lymphoma (pcALCL) and melanoma.

Case presentation

Here we present the case of a patient with concomitant primary cutaneous ALCL and metastatic melanoma, progressing on anti-programmed death (PD)-1 therapy, who developed Kaposi’s varicelliform eruption after receiving the first dose of Talimogene laherparepvec.

Conclusion

This case highlights the complexities of care of patients with coexistent cancers, demonstrates rapid progression of primary cutaneous ALCL on nivolumab and introduces a novel adverse effect of Talimogene laherparepvec.

Complete intracranial response to talimogene laherparepvec (T-Vec), pembrolizumab and whole brain radiotherapy in a patient with melanoma brain metastases refractory to dual checkpoint-inhibition

Background

Immunotherapy, in particular checkpoint blockade, has changed the clinical landscape of metastatic melanoma. Nonetheless, the majority of patients will either be primary refractory or progress over follow up. Management of patients progressing on first-line immunotherapy remains challenging. Expanded treatment options with combination immunotherapy has demonstrated efficacy in patients previously unresponsive to single agent or alternative combination therapy.

Case presentation

We describe the case of a patient with diffusely metastatic melanoma, including brain metastases, who, despite being treated with stereotactic radiosurgery and dual CTLA-4/PD-1 blockade (ipilimumab/nivolumab), developed systemic disease progression and innumerable brain metastases. This patient achieved a complete CNS response and partial systemic response with standard whole brain radiation therapy (WBRT) combined with Talimogene laherparepvec (T-Vec) and pembrolizumab.

Conclusion

Patients who do not respond to one immunotherapy combination may respond during treatment with an alternate combination, even in the presence of multiple brain metastases. Biomarkers are needed to assist clinicians in evidence based clinical decision making after progression on first line immunotherapy to determine whether response can be achieved with second line immunotherapy.

Talimogene laherparepvec: First in class oncolytic virotherapy

Oncolytic viruses represent a novel drug class in which native or modified viruses mediate tumor regression through selective replication within and lysis of tumor cells as well as induction of systemic antitumor immunity capable of eradicating tumor at distant, uninjected sites. Talimogene laherparepvec (TVEC) is a type I herpes simplex virus genetically modified to preferentially replicate in tumor cells, enhance antigen loading of MHC class I molecules and express granulocyte-macrophage colony-stimulating factor to increase tumor-antigen presentation by dendritic cells. It is presently the only oncolytic virus approved by the FDA with an indication for advanced melanoma based upon improved durable response rate in a randomized, phase III trial. Clinical trials are underway in melanoma investigating TVEC as neoadjuvant monotherapy and in combination with checkpoint inhibitors for unresectable disease as well as in an array of other malignancies. It is appropriate to review TVEC's biology mechanism of action, clinical indication and future directions as a prototype of the burgeoning class of oncolytic viruses.

Oncolytic Virotherapy by HSV

Oncolytic virotherapy is a kind of antitumor therapy using viruses with natural or engineered tumor-selective replication to intentionally infect and kill tumor cells. An early clinical trial has been performed in the 1950s using wild-type and non-engineered in vitro-passaged virus strains and vaccine strains (first generation oncolytic viruses). Because of the advances in biotechnology and virology, the field of virotherapy has rapidly evolved over the past two decades and innovative recombinant selectivity-enhanced viruses (second generation oncolytic viruses). Nowadays, therapeutic transgene-delivering "armed" oncolytic viruses (third generation oncolytic viruses) have been engineered using many kinds of viruses. In this chapter, the history, mechanisms, rationality, and advantages of oncolytic virotherapy by herpes simplex virus (HSV) are mentioned. Past and ongoing clinical trials by oncolytic HSVs (G207, HSV1716, NV1020, HF10, Talimogene laherparepvec (T-VEC, OncoVEX^GM-CSF)) are also summarized. Finally, the way of enhancement of oncolytic virotherapy by gene modification or combination therapy with radiation, chemotherapy, or immune checkpoint inhibitors are discussed.

Durable response rate as an endpoint in cancer immunotherapy: insights from oncolytic virus clinical trials

Background

Traditional response criteria may be insufficient to characterize full clinical benefits of anticancer immunotherapies. Consequently, endpoints such as durable response rate (DRR; a continuous response [complete or partial objective response] beginning within 12 months of treatment and lasting ≥6 months) have been employed. There has not, however, been validation that DRR correlates with other more traditional endpoints of clinical benefit such as overall survival.

Methods

We evaluated whether DRR was associated with clinically meaningful measures of benefit (eg, overall survival [OS], quality of life [QoL], or treatment-free interval [TFI]) in a phase 3 clinical trial of an oncolytic virus for melanoma treatment. To evaluate the association between DRR and OS and to mitigate lead time bias, landmark analyses were used. QoL was evaluated using the FACT-BRM questionnaire (comprising the FACT-BRM Physical, Social/Family, Emotional, and Functional well-being domains, the Additional Concerns, Physical and Mental treatment-specific subscales, and the Trial Outcome Index [TOI]). TFI was defined as time from the last study therapy dose to first subsequent therapy dose (including any systemic anticancer therapy for melanoma after study therapy discontinuation).

Results

Four hundred thirty-six patients were included in the intent-to-treat population. Achieving DR was associated with a statistically significant improvement in OS in a landmark analysis at 9 months (HR = 0.07; P = 0.0003), 12 months (HR = 0.05, P < 0.0001), and 18 months (HR = 0.11; P = 0.0002) that persisted after adjusting for disease stage and line of therapy. Achieving a DR was associated with a longer median TFI (HR = 0.33; P = 0.0007) and a higher TOI improvement rate (58.1% versus 30.0%; P = 0.025).

Conclusions

Achieving a DR was associated with clinical benefits such as improved OS and QoL and prolonged TFI, thus supporting the usefulness of DR as a meaningful immunotherapy clinical trial endpoint.

Trial registration

ClinicalTrials.gov identifier, NCT00769704 (https://clinicaltrials.gov/ct2/show/NCT00769704) October 7, 2008

Electronic supplementary material

The online version of this article (doi:10.1186/s40425-017-0276-8) contains supplementary material, which is available to authorized users.

Oncolytic immunotherapy: unlocking the potential of viruses to help target cancer

Oncolytic immunotherapy is a research area of cancer immunotherapy investigating the use of modified viruses to target cancer cells. A variety of different viral backbones (e.g., adenovirus, reovirus) with a diverse range of genetic modifications are currently being investigated for the treatment of a variety of cancers. The oncolytic virus that has advanced the furthest in clinical development is talimogene laherparepvec, a recombinant HSV-1 virus expressing granulocyte-macrophage colony-stimulating factor (GM-CSF). In a phase 3 study in patients with unresectable metastatic melanoma, intralesional talimogene laherparepvec treatment resulted in a higher durable response rate compared with subcutaneous GM-CSF treatment (16.3 versus 2.1%; P < 0.001). Notably, responses were observed at uninjected lesions including visceral lesions, indicating a systemic antitumor response had occurred. Studies evaluating combination treatments involving oncolytic viruses and immunologic agents are ongoing. This review focuses on the mechanisms of action for oncolytic viruses and highlights select agents and combinations currently in development.

Combining talimogene laherparepvec with immunotherapies in melanoma and other solid tumors

Talimogene laherparepvec is a first-in-class intralesional oncolytic immunotherapy. In a recent Phase III trial (OPTiM), talimogene laherparepvec significantly improved durable response rate compared with subcutaneous granulocyte–macrophage colony-stimulating factor (GM-CSF). Overall response rate was also higher in the talimogene laherparepvec arm, and the greatest efficacy was demonstrated in patients with earlier-stage (IIIB, IIIC, or IVM1a) melanoma. Talimogene laherparepvec was well tolerated, with the majority (89%) of adverse events being grade 1 or 2. Preclinical studies have shown that talimogene laherparepvec exerts antitumor activity by selectively replicating within and destroying cancer cells, and through the release of tumor-associated antigens and expression of GM-CSF, which facilitates a wider antitumor immune response. It is hypothesized that combining talimogene laherparepvec with a systemic immunotherapy may, by bringing together complementary mechanisms of action, further enhance the efficacy of both agents. Indeed, talimogene laherparepvec is currently being assessed in combination with immune checkpoint inhibitors, including ipilimumab and pembrolizumab, in trials for melanoma and other solid tumors. Early results in melanoma indicate that the combination of talimogene laherparepvec with ipilimumab or pembrolizumab has greater efficacy than either therapy alone, without additional safety concerns above those expected for each monotherapy. In this review, we discuss the latest results from trials assessing talimogene laherparepvec in combination with other immunotherapies, provide an overview of ongoing and upcoming combination trials, and suggest future directions for talimogene laherparepvec in combination therapy for solid tumors.

Clinical development of talimogene laherparepvec (T-VEC): a modified herpes simplex virus type-1-derived oncolytic immunotherapy

Tumor immunotherapy is emerging as a promising new treatment option for patients with cancer. T-VEC is an intralesional oncolytic virus therapy based on a modified herpes simplex virus type-1. T-VEC selectively targets tumor cells, causing regression in injected lesions and inducing immunologic responses that mediate regression at uninjected/distant sites. In a randomized phase III trial, T-VEC met its primary endpoint of improving the durable response rate vs granulocyte-macrophage colony-stimulating factor in patients with unresectable melanoma. Responses were observed in injected and uninjected regional and visceral lesions. Exploratory analyses suggested survival differences in favor of T-VEC in patients with untreated or stage IIIB/IIIC/IVM1a disease. T-VEC was generally well tolerated, the most common adverse events being flu-like symptoms. Here, we overview recent advances in cancer immunotherapy, focusing on the clinical development of T-VEC, from first-in-human studies and studies in other cancer types, to ongoing combination trials with checkpoint inhibitors.

Indirect Treatment Comparison of Talimogene Laherparepvec Compared with Ipilimumab and Vemurafenib for the Treatment of Patients with Metastatic Melanoma

INTRODUCTION

Few randomized controlled trials have compared new treatments for metastatic melanoma. We sought to examine the relative treatment effect of talimogene laherparepvec compared with ipilimumab and vemurafenib.

METHODS

A systematic literature review of treatments for metastatic melanoma was undertaken but a valid network of evidence could not be established because of a lack of comparative data or studies with sufficient common comparators. A conventional adjusted indirect treatment comparison via network meta-analysis was, therefore, not feasible. Instead, a meta-analysis of absolute efficacy was undertaken, adjusting overall survival (OS) data for differences in prognostic factors between studies using a published algorithm.

RESULTS

Four trials were included in the final indirect treatment comparison: two of ipilimumab, one of vemurafenib, and one of talimogene laherparepvec. Median OS for ipilimumab and vemurafenib increased significantly when adjustment was applied, demonstrating that variation in disease and patient characteristics was biasing OS estimates; adjusting for this made the survival data more comparable. For both ipilimumab and vemurafenib, the adjustments improved Kaplan-Meier OS curves; the observed talimogene laherparepvec OS curve remained above the adjusted OS curves for ipilimumab and vemurafenib, showing that long-term survival could differ from the observed medians.

CONCLUSION

Even with limited data, talimogene laherparepvec, ipilimumab, and vemurafenib could be compared following adjustments, thereby providing a more reliable understanding of the relative effect of treatment on survival in a more comparable patient population. The results of this analysis suggest that OS with talimogene laherparepvec is at least as good as with ipilimumab and vemurafenib and improvement was more pronounced in patients with no bone, brain, lung or other visceral metastases.

FUNDING

Amgen Inc.

Systemic versus local responses in melanoma patients treated with talimogene laherparepvec from a multi-institutional phase II study

Background

We previously reported that talimogene laherparepvec, an oncolytic herpes virus encoding granulocyte-macrophage colony-stimulating factor (GM-CSF), resulted in an objective response rate of 26 % in patients with advanced melanoma in a phase II clinical trial. The response of individual lesions, however, was not reported. Since talimogene laherparepvec is thought to mediate anti-tumor activity through both direct tumor cytolysis and induction of systemic tumor-specific immunity, we sought to determine the independent response rate in virus-injected and non-injected lesions.

Methods

Fifty patients with stage IIIC or IV melanoma were treated with talimogene laherparepvec in a multi-institutional single-arm open-label phase II clinical trial. In this study patients were treated until a complete response was achieved, all accessible tumors disappeared, clinically significant disease progression, or unacceptable toxicity. This report is a post hoc analysis of the systemic effects of talimogene laherparepvec in injected lesions and two types of uninjected lesions—non-visceral lesions and visceral lesions.

Results

Eleven of 23 patients (47.8 %) had a ≥ 30 % reduction in the total burden of uninjected non-visceral lesions, and 2 of 12 patients (16.7 %) had a ≥ 30 % reduction in the total burden of visceral lesions. Among 128 evaluable lesions directly injected with talimogene laherparepvec, 86 (67.2 %) decreased in size by ≥ 30 % and 59 (46.1 %) completely resolved. Of 146 uninjected non-visceral lesions, 60 (41.1 %) decreased in size by ≥ 30 %, the majority of which (44 [30.1 %]) completely resolved. Of 32 visceral lesions, 4 (12.5 %) decreased in size by ≥ 30 %, and 3 (9.4 %) completely resolved. The median time to lesion response was shortest for lesions that were directly injected (18.4 weeks), followed by uninjected non-visceral lesions (23.1 weeks) and visceral lesions (51.3 weeks), consistent with initiation of a delayed regional and systemic anti-tumor immune response to talimogene laherparepvec.

Conclusions

These results support a regional and systemic effect of talimogene laherparepvec immunotherapy in patients with advanced melanoma.

Talimogene laherparepvec (T-VEC) as cancer immunotherapy

Talimogene laherparepvec (T-VEC) is the first-in-class oncolytic virus immunotherapy for the treatment of cancer and was generated from an attenuated, recombinant herpes simplex virus. T-VEC has demonstrated therapeutic activity in melanoma patients and is being tested in a number of other cancers alone and in combination with standard cancer therapeutics and other immunotherapy agents. This review will discuss the current landscape of melanoma, the construction and application of T-VEC for melanoma along with other indications for T-VEC, as well as highlight some of the novel challenges with oncolytic virus immunotherapy as it enters into clinical practice.