Timo Joensuu

Treatment of Cancer Patients With a Serotype 5/3 Chimeric Oncolytic Adenovirus Expressing GMCSF

Augmenting antitumor immunity is a promising way to enhance the potency of oncolytic adenoviral therapy. Granulocyte-macrophage colony-stimulating factor (GMCSF) can mediate antitumor effects by recruiting natural killer cells and by induction of tumor-specific CD8(+) cytotoxic T-lymphocytes. Serotype 5 adenoviruses (Ad5) are commonly used in cancer gene therapy. However, expression of the coxsackie-adenovirus receptor is variable in many advanced tumors and preclinical data have demonstrated an advantage for replacing the Ad5 knob with the Ad3 knob. Here, a 5/3 capsid chimeric and p16-Rb pathway selective oncolytic adenovirus coding for GMCSF was engineered and tested preclinically. A total of 21 patients with advanced solid tumors refractory to standard therapies were then treated intratumorally and intravenously with Ad5/3-D24-GMCSF, which was combined with low-dose metronomic cyclophosphamide to reduce regulatory T cells. No severe adverse events occurred. Analysis of pretreatment samples of malignant pleural effusion and ascites confirmed the efficacy of Ad5/3-D24-GMCSF in transduction and cell killing. Evidence of biological activity of the virus was seen in 13/21 patients and 8/12 showed objective clinical benefit as evaluated by radiology with Response Evaluation Criteria In Solid Tumors (RECIST) criteria. Antiadenoviral and antitumoral immune responses were elicited after treatment. Thus, Ad5/3-D24-GMCSF seems safe in treating cancer patients and promising signs of efficacy were seen.

Oncolytic Adenovirus Coding for Granulocyte Macrophage Colony-Stimulating Factor Induces Antitumoral Immunity in Cancer Patients

Granulocyte macrophage colony-stimulating factor (GMCSF) can mediate antitumor effects by recruiting natural killer cells and by induction of tumor-specific cytotoxic T-cells through antigen-presenting cells. Oncolytic tumor cell-killing can produce a potent costimulatory danger signal and release of tumor epitopes for antigen-presenting cell sampling. Therefore, an oncolytic adenovirus coding for GMCSF was engineered and shown to induce tumor-specific immunity in an immunocompetent syngeneic hamster model. Subsequently, 20 patients with advanced solid tumors refractory to standard therapies were treated with Ad5-D24-GMCSF. Of the 16 radiologically evaluable patients, 2 had complete responses, 1 had a minor response, and 5 had disease stabilization. Responses were frequently seen in injected and noninjected tumors. Treatment was well tolerated and resulted in the induction of both tumor-specific and virus-specific immunity as measured by ELISPOT and pentamer analysis. This is the first time that oncolytic virus-mediated antitumor immunity has been shown in humans. Ad5-D24-GMCSF is promising for further clinical testing.

Immunological Effects of Low-dose Cyclophosphamide in Cancer Patients Treated With Oncolytic Adenovirus

Patients with advanced solid tumors refractory to and progressing after conventional therapies were treated with three different regimens of low-dose cyclophosphamide (CP) in combination with oncolytic adenovirus. CP was given with oral metronomic dosing (50 mg/day, N = 21), intravenously (single 1,000 mg dose, N = 7) or both (N = 7). Virus was injected intratumorally. Controls (N = 8) received virus without CP. Treatments were well tolerated and safe regardless of schedule. Antibody formation and virus replication were not affected by CP. Metronomic CP (oral and oral + intravenous schedules) decreased regulatory T cells (T(regs)) without compromising induction of antitumor or antiviral T-cell responses. Oncolytic adenovirus given together with metronomic CP increased cytotoxic T cells and induced Th1 type immunity on a systemic level in most patients. All CP regimens resulted in higher rates of disease control than virus only (all P < 0.0001) and the best progression-free (PFS) and overall survival (OS) was seen in the oral + intravenous group. One year PFS and OS were 53 and 42% (P = 0.0016 and P < 0.02 versus virus only), respectively, both which are unusually high for chemotherapy refractory patients. We conclude that low-dose CP results in immunological effects appealing for oncolytic virotherapy. While these first-in-human data suggest good safety, intriguing efficacy and extended survival, the results should be confirmed in a randomized trial.

2-weekly versus 3-weekly docetaxel to treat castration-resistant advanced prostate cancer: a randomised, phase 3 trial

BACKGROUND Docetaxel administered every 3 weeks is a standard treatment for castration-resistant advanced prostate cancer. We hypothesised that 2-weekly administration of docetaxel would be better tolerated than 3-weekly docetaxel in patients with castration-resistant advanced prostate cancer, and did a prospective, multicentre, randomised, phase 3 study to compare efficacy and safety. METHODS Eligible patients had advanced prostate cancer (metastasis, a prostate-specific-antigen test result of more than 10·0 ng/mL, and WHO performance status score of 0-2), had received no chemotherapy (except with estramustine), had undergone surgical or chemical castration, and had been referred to a treatment centre in Finland, Ireland, or Sweden. Enrolment and treatment were done between March 1, 2004, and May 31, 2009. Randomisation was done centrally and stratified by centre and WHO performance status score of 0-1 vs 2. Patients were assigned 75 mg/m(2) docetaxel intravenously on day 1 of a 3-week cycle, or 50 mg/m(2) docetaxel intravenously on days 1 and 15 of a 4-week cycle. 10 mg oral prednisolone was administered daily to all patients. The primary endpoint was time to treatment failure (TTTF). We assessed data in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT00255606. FINDINGS 177 patients were randomly assigned to the 2-weekly docetaxel group and 184 to the 3-weekly group. 170 patients in the 2-weekly group and 176 in the 3-weekly group were included in the analysis. The 2-weekly administration was associated with significantly longer TTTF than was 3-weekly administration (5·6 months, 95% CI 5·0-6·2 vs 4·9 months, 4·5-5·4; hazard ratio 1·3, 95% CI 1·1-1·6, p=0·014). Grade 3-4 adverse events occurred more frequently in the 3-weekly than in the 2-weekly administration group, including neutropenia (93 [53%] vs 61 [36%]), leucopenia (51 [29%] vs 22 [13%]), and febrile neutropenia (25 [14%] vs six [4%]). Neutropenic infections were reported more frequently in patients who received docetaxel every 3 weeks (43 [24%] vs 11 [6%], p=0·002). INTERPRETATION Administration of docetaxel every 2 weeks seems to be well tolerated in patients with castration-resistant advanced prostate cancer and could be a useful option when 3-weekly single-dose administration is unlikely to be tolerated. FUNDING Sanofi.

Oncolytic adenovirus with temozolomide induces autophagy and antitumor immune responses in cancer patients.

Oncolytic adenoviruses and certain chemotherapeutics can induce autophagy and immunogenic cancer cell death. We hypothesized that the combination of oncolytic adenovirus with low-dose temozolomide (TMZ) is safe, effective, and capable of inducing antitumor immune responses. Metronomic low-dose cyclophosphamide (CP) was added to selectively reduce regulatory T-cells. Preclinically, combination therapy inhibited tumor growth, increased autophagy, and triggered immunogenic cell death as indicated by elevated calreticulin, adenosine triphosphate (ATP) release, and nuclear protein high-mobility group box-1 (HMGB1) secretion. A total of 41 combination treatments given to 17 chemotherapy-refractory cancer patients were well tolerated. We observed anti- and proinflammatory cytokine release, evidence of virus replication, and induction of neutralizing antibodies. Tumor cells showed increased autophagy post-treatment. Release of HMGB1 into serum--a possible indicator of immune response--increased in 60% of treatments, and seemed to correlate with tumor-specific T-cell responses, observed in 10/15 cases overall (P = 0.0833). Evidence of antitumor efficacy was seen in 67% of evaluable treatments with a trend for increased survival over matched controls treated with virus only. In summary, the combination of oncolytic adenovirus with low-dose TMZ and metronomic CP increased tumor cell autophagy, elicited antitumor immune responses, and showed promising safety and efficacy.

Oncolytic Adenovirus ICOVIR-7 in Patients with Advanced and Refractory Solid Tumors

Purpose: Twenty-one patients with cancer were treated with a single round of oncolytic adenovirus ICOVIR-7. Experimental Design: ICOVIR-7 features an RGD-4C modification of the fiber HI-loop of serotype 5 adenovirus for enhanced entry into tumor cells. Tumor selectivity is mediated by an insulator, a modified E2F promoter, and a Rb-binding site deletion of E1A, whereas replication is optimized with E2F binding hairpins and a Kozak sequence. ICOVIR-7 doses ranged from 2 × 1010 to 1 × 1012 viral particles. All patients had advanced and metastatic solid tumors refractory to standard therapies. Results: ICOVIR-7 treatment was well tolerated with mild to moderate fever, fatigue, elevated liver transaminases, chills, and hyponatremia. One patient had grade 3 anemia but no other serious side effects were seen. At baseline, 9 of 21 of patients had neutralizing antibody titers against the ICOVIR-7 capsid. Treatment resulted in neutralizing antibody titer induction within 4 weeks in 16 of 18 patients. No elevations of serum proinflammatory cytokine levels were detected. Viral genomes were detected in the circulation in 18 of 21 of patients after injection and 7 of 15 of the samples were positive 2 to 4 weeks later suggesting viral replication. Conclusions: Overall, objective evidence of antitumor activity was seen in 9 of 17 evaluable patients. In radiological analyses, 5 of 12 evaluable patients had stabilization or reduction in tumor size. These consisted of one partial response, two minor responses and two cases of stable disease, all occurring in patients who had progressive disease before treatment. In summary, ICOVIR-7 treatment is apparently safe, resulting in anticancer activity, and is therefore promising for further clinical testing. Clin Cancer Res; 16(11); 3035–43. ©2010 AACR.

Integrin targeted oncolytic adenoviruses Ad5‐D24‐RGD and Ad5‐RGD‐D24‐GMCSF for treatment of patients with advanced chemotherapy refractory solid tumors

The safety of oncolytic viruses for treatment of cancer has been shown in clinical trials while antitumor efficacy has often remained modest. As expression of the coxsackie‐adenovirus receptor may be variable in advanced tumors, we developed Ad5‐D24‐RGD, a p16/Rb pathway selective oncolytic adenovirus featuring RGD‐4C modification of the fiber. This allows viral entry through alpha‐v‐beta integrins frequently highly expressed in advanced tumors. Advanced tumors are often immunosuppressive which results in lack of tumor eradication despite abnormal epitopes being present. Granulocyte‐macrophage colony stimulating factor (GMCSF) is a potent activator of immune system with established antitumor properties. To stimulate antitumor immunity and break tumor associated immunotolerance, we constructed Ad5‐RGD‐D24‐GMCSF, featuring GMCSF controlled by the adenoviral E3 promoter. Preliminary safety of Ad5‐D24‐RGD and Ad5‐RGD‐D24‐GMCSF for treatment of human cancer was established. Treatments with Ad5‐D24‐RGD (N = 9) and Ad5‐RGD‐D24‐GMCSF (N = 7) were well tolerated. Typical side effects were grade 1‐2 fatigue, fever and injection site pain. 77% (10/13) of evaluable patients showed virus in circulation for at least 2 weeks. In 3 out of 6 evaluable patients, disease previously progressing stabilized after a single treatment with Ad5‐RGD‐D24‐GMCSF. In addition, 2/3 patients had stabilization or reduction in tumor marker levels. All patients treated with Ad5‐D24‐RGD showed disease progression in radiological analysis, although 3/6 had temporary reduction or stabilization of marker levels. Induction of tumor and adenovirus specific immunity was demonstrated with ELISPOT in Ad5‐RGD‐D24‐GMCSF treated patients. RGD modified oncolytic adenoviruses with or without GMCSF seem safe for further clinical development.

Comparison of granulocyte-macrophage colony-stimulating factor and sucralfate mouthwashes in the prevention of radiation-induced mucositis: a double-blind prospective randomized phase III study

PURPOSE To compare granulocyte-macrophage colony-stimulating factor (GM-CSF) mouthwashes with sucralfate mouthwashes in the prevention of radiation-induced mucositis. METHODS AND MATERIALS Forty patients with radically operated head-and-neck cancer were randomly allocated to use either GM-CSF (n = 21) or sucralfate (n = 19) mouthwashes during postoperative radiotherapy (RT). All patients received conventionally fractionated RT to a total dose of 50-60 Gy in 2-Gy daily fractions during 5-6 weeks to the primary site and regional lymphatics. A minimum of 50% of the oral cavity and oropharyngeal mucosa was included in the clinical target volume. GM-CSF mouthwashes consisted of 37.5 microg GM-CSF and sucralfate mouthwashes of 1.0 g of sucralfate distilled in water. Both washes were used 4 times daily, beginning after the first week of RT and continued to the end of the RT course. Symptoms related to radiation mucositis and body weight, serum prealbumin level, and blood cell counts were monitored weekly. RESULTS Oral mucositis tended to be less severe in the GM-CSF group (p = 0.072). Complete (n = 1) or partial (n = 4) healing of mucositis occurred during the RT course in 5 patients (24%) in the GM-CSF group and in none of the patients in the sucralfate group (p = 0.049). Patients who received GM-CSF had less mucosal pain (p = 0.058) and were less often prescribed opioids for pain (p = 0.042). Three patients in the sucralfate group needed hospitalization for mucositis during RT compared with none in the GM-CSF group. Four patients (21%) in the sucralfate group and none in the GM-CSF group required an interruption in the RT course (p = 0.042). No significant differences in weight, prealbumin level, or blood cell count were found between the groups, and both mouthwashes were well tolerated. CONCLUSION GM-CSF mouthwashes may be moderately more effective than sucralfate mouthwashes in preventing radiation-induced mucositis and mucositis-related pain, and their use may lead to less frequent RT course interruptions from mucositis. The present findings need to be confirmed before adopting GM-CSF mouthwashes in routine clinical use.

Ad3-hTERT-E1A, a Fully Serotype 3 Oncolytic Adenovirus, in Patients With Chemotherapy Refractory Cancer

Twenty-five patients with chemotherapy refractory cancer were treated with a fully serotype 3-based oncolytic adenovirus Ad3-hTERT-E1A. In mice, Ad3 induced higher amounts of cytokines but less liver damage than Ad5 or Ad5/3. In humans, the only grade 3 adverse reactions were self-limiting cytopenias and generally the safety profile resembled Ad5-based oncolytic viruses. Patients that had been previously treated with Ad5 viruses presented longer lasting lymphocytopenia but no median increase in Ad3-specific T-cells in blood, suggesting immunological activity against antigens other than Ad3 hexon. Frequent alterations in antitumor T-cells in blood were seen regardless of previous virus exposure. Neutralizing antibodies against Ad3 increased in all patients, whereas Ad5 neutralizing antibodies remained stable. Treatment with Ad3-hTERT-E1A resulted in re-emergence of Ad5 viruses from previous treatments into blood and vice versa. Signs of possible efficacy were seen in 11/15 (73%) patients evaluable for tumor markers, four of which were treated only intravenously. Particularly promising results were seen in breast cancer patients and especially those receiving concomitant trastuzumab. Taken together, Ad3-hTERT-E1A seems safe for further clinical testing or development of armed versions. It offers an immunologically attractive alternative, with possible pharmacodynamic differences and a different receptor compared to Ad5.

Oncolytic adenovirus treatment of a patient with refractory neuroblastoma

1Cancer Gene Therapy Group, Transplantation Laboratory and Finnish Institute of Molecular Medicine, University of Helsinki, Finland, 2HUSLAB, Helsinki University Central Hospital, Finland, 3Haartman Institute, University of Helsinki, Finland, 4Department of Pathology, Helsinki University Central Hospital, Finland, 5Department of Obstetrics and Gynecology, Duesseldorf University Medical Center, Heinrich-Heine University, Germany, 6Helsinki Medical Imaging Center, University of Helsinki, Finland, 7Department of Anesthesiology, Helsinki University Central Hospital, Finland, 8Genome Scale Biology Program, Biomedicum Helsinki, Finland, 9Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Finland and 10Docrates Oncology Hospital, Helsinki, Finland