A phase 1 study of regorafenib and sildenafil in adults with advanced solid tumors

The purpose of this study is to establish the recommended phase 2 dose for regorafenib in combination with sildenafil for patients with advanced solid tumors. Secondary outcomes included identification of antitumor effects of regorafenib and sildenafil, toxicity of the combination, determination of PDE5 expression in tumor samples, and the impact of sildenafil on the pharmacokinetics of regorafenib. This study was a phase 1, open-label single-arm dose-escalation trial using a 3 + 3 design. Additional patients were enrolled at the maximum tolerated dose (MTD) until a total of 12 patients were treated at the MTD. A total of 29 patients were treated in this study. The median duration of treatment was 8 weeks. The recommended phase 2 doses determined in this study are regorafenib 160 mg daily with sildenafil 100 mg daily. The most common toxicities included palmar-plantar erythrodysesthesia syndrome (20 patients, 69%) and hypophosphatemia (18 patients, 62%). Two patients (7%) experienced grade 4 lipase increase. Objective responses were not observed; however, 14 patients (48%) had a period of stable disease during the study. Stable disease for up to 12 months was observed in patients with ovarian cancer as well as up to 20 months for a patient with cervical cancer. The combination of regorafenib and sildenafil at the recommended phase 2 dose is safe and generally well tolerated. Disease control in patients with gynecologic malignancies was especially encouraging. Further evaluation of the combination of regorafenib and sildenafil in gynecologic malignancies is warranted. Clinical Trial Registration Number: NCT02466802.

Final survival follow-up and translational associations using interval indirect immunization with oregovomab (O) and poly ICLC in patients (pts) with recurrent platinum-resistant ovarian cancer (PROC)

e17545

Background: Indirect immunization with tumor specific antibody is an approach to triggering therapeutic immunity to cancer through activated immune cells. O is a monoclonal IgG1 specific to CA125 (MUC16). O is currently in phase III evaluation of front-line chemoimmunotherapy (CIT), having shown benefit relative to chemotherapy alone in a randomized phase II study (Brewer, Gyn Onc 2020). H is a TLR3 agonist used as a stimulatory immune adjuvant. The dosing phase of the protocol established safety and compatibility of this combination. The primary safety and response outcomes were reported at IGCS-2019. Immune parameters and long-term outcome associations are the focus of this final update. Methods: Pts with heavily treated RECIST evaluable platinum resistant ovarian cancer (median of 5 prior Rx) received 4 IV infusions with 2 mg O followed by 2mg H IM 30 min & 48 hrs post O at wks 0, 3, 6, 9. At wk 12 imaging was performed and elective salvage Rx allowed. A fifth O+H was optional at wk 16. Study endpoints included immune associations after O+H, after second-line chemotherapy, and survival outcomes. Results: 17 pts were enrolled at 2 centers; 15 patients were dosed and 13 completed the specified minimum 3 infusions. The treatment was well tolerated with local reactions and mild flu like symptoms (13/15 pts) as the only reported adverse events. There was no treatment related serious adverse events. Median survival was 15.0 m [95% CI:10.8m-NE] and 4 patients remained alive at data lock (median 26.5 m). H stimulated an early humoral antibody response to O at wk 6 in 7 of 9 pts (78%). Interval administration of second-line Rx (bevacizumab, paclitaxel, carboplatin, &/or doxorubicin) and O were associated with further antibody spikes. Baseline neutrophil monocyte to lymphocyte ratio (NMLR), a measure of myeloid-derived immune suppression was inversely associated with survival. PROC patients with baseline NMLR ≤4x (n = 8) had median OS 19.6m [15.0 m -NE] vs median OS 10.8m [3.6m-NE] HR 2.44 [0.73-8.15], ( p= 0.13) for pts with NMLR > 4.0 (n = 7). Conclusions: H is a viable immune adjuvant for combination with O suitable for further study in immune resistant settings. Immune responsiveness was similar to that observed in a prior study of same day schedule of carboplatin-paclitaxel front-line immunotherapy (Braly, JIT 2009; Battaglia, Cll, 2020). Patterns of immune response to O in the setting of recurrent ovarian cancer are influenced by concomitant anti-neoplastic therapy. Clinical outcomes appear sensitive to myeloid burden (NMLR > 4) which may be more prevalent in patients with treatment resistant disease than in chemotherapy naïve patients, as previously observed in front-line CIT trials. A phase III study to further evaluate these associations in the front-line setting is currently underway NCT04498117. Clinical trial information: NCT03162562.

A phase 1 study of neoadjuvant chemotherapy followed by concurrent chemoradiation with gemcitabine, sorafenib, and vorinostat in pancreatic cancer

e16268

Background: The multi-kinase inhibitor sorafenib (S) and HDAC inhibitor vorinostat (V) demonstrated synergism against preclinincal pancreatic cancer (PaCa) models. The combination of S & V also potently radiosensitized pancreatic cancer cells and enhanced the activity of gemcitabine (G). This led to a phase 1 trial to determine the doses and schedule appropriate for phase 2 study of S & V with weekly G and intensity modulated radiotherapy (IMRT) as neoadjuvant treatment of PaCa following chemotherapy. Methods: Using a 3+3 dose-escalation design, adult patients with resectable, borderline resectable, unresectable, and lymph node positive PaCa were enrolled to 6 dose levels. Enrolled patients had completed at least 8w of neoadjuvant chemotherapy prior to IMRT. The schedule of administration was weekly 200mg/m2 G weekly during IMRT, S & V were dosed either 3x or 5x weekly during IMRT. Primary endpoint was to identify the dose and schedule for S & V with G based chemoradiation. Key secondary endpoints included antitumor activity, R0 resection rate, OS. Correlative studies to evaluate a variety of biomarkers and Nanostring expression analysis on pre- and post-therapy tumor specimens were also performed. Results: 22 patients were enrolled and 21 treated at 6 dose levels. Due to thrombocytopenia limiting drug exposure, the trial was modified to reduce G to 200mg/m2/wk and S & V to 3 d/wk instead of 5 d/wk. 13 patients were eligible for surgery, and 9 had R0 resections. Conclusions: Our findings indicate that the study regimen was well tolerated, typical toxicities of S (hand foot syndrome) were not observed with intermittent dosing. Uncomplicated cytopenias limited drug exposure, which was improved with intermittent S&V dosing. The RP2D of the combination is S (400mg po BID 3d/wk), V (200mg po qd 3d/wk), G 200mg/m2 IV weekly, with IMRT (50.4 Gy over 28 fractions, 5d/wk). Antitumor activity was observed across dose levels, with an encouraging R0 resection rate. These results warrant further investigation of combining S and V with G and IMRT as neoadjuvant treatment of PaCa following chemotherapy. Analyses of correlative studies and OS are underway. Clinical trial information: NCT02349867. [Table: see text]

Phase I study of regorafenib and sildenafil in advanced solid tumors

3593

Background: Regorafenib (R) is an oral multikinase inhibitor with anti-angiogenic properties approved for use in several solid tumors. Sildenafil (S) is an oral phosphodiesterase-5 (PDE5) inhibitor that interacts synergistically with R in both short-term and colony formation assays to kill multiple cancer cell types. Mechanistic studies identified that PDE5 knockdown enhances R lethality, suggesting a direct target effect for S. Methods: A single-center, open-label, dose-escalation study was conducted in adults with advanced solid tumors. Patients (pts) took R (120 or 160 mg) and S (50 or 100 mg) once daily days 1 through 21 of each 28-day cycle. Pts remained on study treatment until progression or excessive toxicity, with response assessments every 8 wks. The maximum tolerated dose (MTD) was defined as the maximum tested dose with ≤1/6 pts experiencing dose-limiting toxicity (DLT), with Cycle 1 as the DLT observation period. Results: 32 pts were enrolled and 29 treated at 3 dose levels (DLs). Median duration of treatment was 8 (range 2 – 101) wks. One of 6 evaluable pts treated at DL2 (160 mg R + 50 mg S) experienced DLT (grade 4 lipase increase). One of 12 evaluable pts treated at DL3A (160 mg R + 100 mg S, the MTD) experienced DLT (grade 3 rash and grade 3 muscle pain). The toxicity profile was generally consistent with that seen in R monotherapy at FDA-approved doses. 10 pts had a best response of progressive disease (PD). 14 pts had a best response of stable disease (SD), 5 of whom had stable disease duration > 24 wks. 5 treated pts were not evaluable for response. Notably, 2 pts with ovarian cancer and 1 with cervical cancer had stable disease > 24 wks. Analyses of correlative studies to examine pharmacokinetics and drug combination pharmacodynamic effects are underway. Conclusions: The combination was well-tolerated. The recommended phase 2 dose is 160 mg R + 100 mg S. Objective responses were not observed, but prolonged stable disease was seen in a subset of pts. Encouraging disease control was seen in gynecologic cancers. Dosing up to 100 mg S is safe concurrently with standard doses of R, and may be considered as an adjunct to R in future trials. Evaluation of R+S in gynecologic cancers warrants further consideration. Clinical trial information: NCT02466802 . [Table: see text]

Gynecologic oncology, gender and relevant leadership in academic medicine

e19056

Background: Within academic medicine, there has been increasing attention to diversity and inclusion. We sought to characterize gynecologic oncologist (GO) faculty inclusion, with attention to gender in relevant academic leadership roles. Methods: Using the American Association of Medical Colleges list of accredited schools of medicine academic institutions were identified. Observational data was obtained through institutional websites in 2019. Results: Of 154 accredited medical schools, 144 contain a department of obstetrics and gynecology (OBG) with a chair; 103 a GO division with a director; 98 a clinical cancer center with a director. GO divisions included an average of 3.1 faculty. 55% of GO faculty were women, compared to 66% of OBG faculty (p < 0.01). 38% of the GO division directors were women which was an under-representation (p < 0.01). GOs made up 10% of OBG faculty and 15.4% of OBG chairs (NS). Women GOs made up 7.9% of women OBG faculty and 8 (5.6%) women GOs were OBG chairs (NS). 9.9% of GO faculty (11.6% of women GO faculty) report to women GOs at the chair level. OBG departments with a GO chair were more likely to have a woman GO division director (68.4 vs 31.7%, p < 0.01), and GO fellowship (59.1 vs 32%, p < 0.01). The majority (59%) of cancer centers directors were medical oncologists (see Table). 2 (2%) of cancer center directors were GOs; 1 at an NCI designated cancer center. Neither GO directors were women. Incidence to leadership and mortality to leadership ratios were calculated compared to expected rates by SEER 2019. By these measures GOs were underrepresented in cancer center leadership (p < 0.01, p < 0.01). Conclusions: Despite representative leadership of GO and women GO within in OBG leadership, most GOs report to non-oncologists at the department chair level. Potential benefits of GO leadership within OBG departments were identified. The practice of gynecologic oncology includes complex medical and surgical cancer care making these physicians uniquely qualified for cancer center, but representation of GOs in cancer center leadership is low and women GO were absent from cancer center director positions. Without inclusion of GO in cancer center leadership, existing inequities in clinical care, research and funding for gynecologic malignancies may be amplified. [Table: see text]

A randomized phase II evaluation of weekly gemcitabine plus pazopanib versus weekly gemcitabine alone in the treatment of persistent or recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma

OBJECTIVE

Angiogenesis inhibition is a valuable strategy for ovarian cancer (EOC). Pazopanib (paz) is a potent small molecular inhibitor of VEGF-1, -2, -3, PDGFR, c-kit, and has activity as a single agent in ovarian cancer. We designed a trial to assess the benefit of adding paz to gemcitabine (gem) in patients with recurrent EOC.

METHODS

An open-label, randomized, multi-site, phase 2 trial was conducted (NCT01610206) including patients with platinum resistant or sensitive disease, ≤ 3 prior lines of chemotherapy, and measurable/evaluable disease. Patients were randomly assigned to weekly gem 1000 mg/m² on days 1 and 8 of a 21 day cycle, with or without paz 800 mg QD, stratified by platinum sensitivity and number of prior lines (1 vs 2 or 3). The primary endpoint was PFS.

RESULTS

148 patients were enrolled 2012-2017. Median age was 63 years (30-82); 60% were platinum resistant; median surveillance was 13 months (0.4-54 months). Median PFS was 5.3 (95% CI, 4.2-5.8) vs 2.9 months (95% CI, 2.1-4.1) in the gem arm. The PFS effect was most pronounced in the platinum resistant group (5.32 vs 2.33 months Tarone-Ware p < 0.001). There was no difference in OS. Overall RR (PR 20% vs 11%, Chi-squre p = 0.02) and DCR (80% vs 60%, Chi-square p < 0.001) were higher in the combination. High grade AEs in the combination arm included ≥ Grade 3: hypertension (15%), neutropenia (35%), and thrombocytopenia (12%).

CONCLUSIONS

The addition of paz to gem enhanced anti-tumor activity; those with platinum-resistant disease derived the most benefit from combination therapy, even in the setting of receiving prior bevacizumab.

A Randomized Phase II Trial of Epigenetic Priming with Guadecitabine and Carboplatin in Platinum-resistant, Recurrent Ovarian Cancer

PURPOSE

Platinum resistance in ovarian cancer is associated with epigenetic modifications. Hypomethylating agents (HMA) have been studied as carboplatin resensitizing agents in ovarian cancer. This randomized phase II trial compared guadecitabine, a second-generation HMA, and carboplatin (G+C) against second-line chemotherapy in women with measurable or detectable platinum-resistant ovarian cancer.

PATIENTS AND METHODS

Patients received either G+C (guadecitabine 30 mg/m² s.c. once-daily for 5 days and carboplatin) or treatment of choice (TC; topotecan, pegylated liposomal doxorubicin, paclitaxel, or gemcitabine) in 28-day cycles until progression or unacceptable toxicity. The primary endpoint was progression-free survival (PFS); secondary endpoints were RECIST v1.1 and CA-125 response rate, 6-month PFS, and overall survival (OS).

RESULTS

Of 100 patients treated, 51 received G+C and 49 received TC, of which 27 crossed over to G+C. The study did not meet its primary endpoint as the median PFS was not statistically different between arms (16.3 weeks vs. 9.1 weeks in the G+C and TC groups, respectively; P = 0.07). However, the 6-month PFS rate was significantly higher in the G+C group (37% vs. 11% in TC group; P = 0.003). The incidence of grade 3 or higher toxicity was similar in G+C and TC groups (51% and 49%, respectively), with neutropenia and leukopenia being more frequent in the G+C group.

CONCLUSIONS

Although this trial did not show superiority for PFS of G+C versus TC, the 6-month PFS increased in G+C treated patients. Further refinement of this strategy should focus on identification of predictive markers for patient selection.

Differences in presentation and survival of Asians compared to Caucasians with ovarian cancer: An NRG Oncology/GOG Ancillary study of 7914 patients

PURPOSE

To compare patient/tumor characteristics and outcomes of Asians to Caucasian patients with epithelial ovarian cancer.

METHODS

Ancillary data were pooled and analyzed from ten prospective randomized front-line Gynecologic Oncology Group clinical trials from 1996 to 2011. Demographic, clinicopathologic features, disease-specific and all-cause survival were analyzed.

RESULTS

Of 7914 patients, 7641 were Caucasian and 273 Asian. When compared to Caucasians, Asians were younger at trial enrollment, had a better performance status, earlier-stage cancers (17.2% vs. 8.1% with stage I; p < 0.001), and were more likely to be of clear cell (15.8% vs. 6.2%, p < 0.001) and mucinous (3.3% vs. 1.9%, p < 0.001) histology. Asians had an improved 5-year disease-specific survival of 54.1% compared to 46.1% for Caucasians, p = 0.001. In multivariate analysis, the Asian race remained a significant prognostic factor for all-cause survival (HR: 0.84; 95% CI: 0.72-0.99; p = 0.04). Other factors predictive of improved survival included younger age, better performance status, optimal cytoreduction, earlier stage, non-clear cell histology, and lower grade tumors.

CONCLUSION

Asians enrolled into phase III ovarian cancer clinical trials were younger, with better performance status, earlier-stage of disease, and have a greater number of clear cell and mucinous tumors. After adjusting for these prognostic factors, Asians have a better survival compared to Caucasians.

Co-occurring substance use disorder: The impact on treatment adherence in women with locally advanced cervical cancer

The purpose of this study was to identify the prevalence of substance use disorder and its association with adherence to treatment and survival in locally advanced cervical cancer patients treated with primary radiation therapy. This is a retrospective case series of locally advanced cervical cancer patients with substance use disorder in a single academic institution treated with radiation therapy between 2005 and 2016. Substance use disorder was identified through chart review. Those with substance use disorder were compared to those without in regards to demographics, Charlson comorbidity index, treatment details and outcomes. Of the 129 patients with locally advanced cervical cancer, 16 (12.4%) were identified as having substance use disorder. Patients with substance use disorder were younger (42.1 years vs 51.5 years, p = .013) and more likely to be smokers (81.3% vs 42.5%, p = .004). The majority of patients with substance use disorder received concurrent chemotherapy (93.8%) and brachytherapy in addition to external beam radiation therapy (81.3%). There was no significant difference in days to completion of radiation therapy between patients with and without substance use disorder. Radiation dose received, toxicities and survival were similar between groups. Among cervical cancer patients receiving treatment with radiation therapy, substance use disorder was not associated with poorer adherence, longer radiation treatment times or a difference in total dose of radiation received. Our experience demonstrates that patients with substance use disorder are able to adhere to complex, multimodal treatment plans resulting in similar cancer specific outcomes compared to patients without substance use disorder.

•

Substance abuse disorder is common among locally advanced cervical cancer patients.

•

Treatment adherence is similar in patients with and without substance use disorder.

•

Treatment plan should not be altered based on a substance use disorder comorbidity.

Randomized phase II study of the PDGFRα antibody olaratumab plus liposomal doxorubicin versus liposomal doxorubicin alone in patients with platinum-refractory or platinum-resistant advanced ovarian cancer

BACKGROUND

Olaratumab is a platelet-derived growth factor receptor-α (PDGFRα)-targeting monoclonal antibody blocking PDGFRα signaling. PDGFRα expression is associated with a more aggressive phenotype and poor ovarian cancer outcomes. This randomized, open label phase II study evaluated olaratumab plus liposomal doxorubicin compared with liposomal doxorubicin alone in advanced ovarian cancer patients.

METHODS

Patients with platinum-refractory or platinum-resistant advanced ovarian cancer were randomized 1:1 to receive liposomal doxorubicin (40 mg/m², intravenous infusion) administered every 4 weeks with or without olaratumab (20 mg/kg, IV infusion) every 2 weeks. Patients were stratified based on prior response to platinum therapy (refractory vs resistant). The primary efficacy endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate, duration of response, and safety.

RESULTS

A total of 123 patients were treated (62 olaratumab+liposomal doxorubicin; 61 liposomal doxorubicin). Median PFS was 4.2 months for olaratumab+liposomal doxorubicin and 4.0 months for liposomal doxorubicin (stratified hazard ratio [HR] = 1.043; 95% confidence interval [CI] 0.698-1.558; p = 0.837). Median OS was 16.6 months and 16.2 months in the olaratumab+liposomal doxorubicin and liposomal doxorubicin arms, respectively (HR = 1.098; 95% CI 0.71-1.71). In the platinum-refractory subgroup, median PFS was 5.5 months (95% CI 1.6-9.2) and 3.7 months (95% CI 1.9-9.2) in the olaratumab+liposomal doxorubicin (n = 15) and liposomal doxorubicin arms (n = 16), respectively (HR = 0.85; 95% CI 0.38-1.91). Overall, 59.7% (olaratumab+liposomal doxorubicin) and 65.6% (liposomal doxorubicin) of patients reported grade ≥ 3 adverse events regardless of causality. The most common treatment-emergent adverse events (all grades) regardless of causality were fatigue related (61%), nausea (57%), and constipation (52%) with olaratumab+liposomal doxorubicin and nausea (64%), fatigue related (62%), and mucositis (46%) with liposomal doxorubicin.

CONCLUSIONS

The addition of olaratumab to liposomal doxorubicin did not result in significant prolongation of PFS or OS in platinum-resistant or platinum-refractory ovarian cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00913835 ; registered June 2, 2009.

Phase I study of pemetrexed with sorafenib in advanced solid tumors

Purpose

To determine if combination treatment with pemetrexed and sorafenib is safe and tolerable in patients with advanced solid tumors.

Results

Thirty-seven patients were enrolled and 36 patients were treated (24 in cohort A; 12 in cohort B). The cohort A dose schedule resulted in problematic cumulative toxicity, while the cohort B dose schedule was found to be more tolerable. The maximum tolerated dose (MTD) was pemetrexed 750 mg/m² every 14 days with oral sorafenib 400 mg given twice daily on days 1–5. Because dosing delays and modifications were associated with the MTD, the recommended phase II dose was declared to be pemetrexed 500 mg/m² every 14 days with oral sorafenib 400 mg given twice daily on days 1–5. Thirty-three patients were evaluated for antitumor activity. One complete response and 4 partial responses were observed (15% overall response rate). Stable disease was seen in 15 patients (45%). Four patients had a continued response at 6 months, including 2 of 5 patients with triple-negative breast cancer.

Experimental Design

A phase I trial employing a standard 3 + 3 design was conducted in patients with advanced solid tumors. Cohort A involved a novel dose escalation schema exploring doses of pemetrexed every 14 days with continuous sorafenib. Cohort B involved a modified schedule of sorafenib dosing on days 1–5 of each 14-day pemetrexed cycle. Radiographic assessments were conducted every 8 weeks.

Conclusions

Pemetrexed and intermittent sorafenib therapy is a safe and tolerable combination for patients, with promising activity seen in patients with breast cancer.

The afatinib resistance of in vivo generated H1975 lung cancer cell clones is mediated by SRC/ERBB3/c-KIT/c-MET compensatory survival signaling

We generated afatinib resistant clones of H1975 lung cancer cells by transient exposure of established tumors to the drug and collected the re-grown tumors. Afatinib resistant H1975 clones did not exhibit any additional mutations in proto-oncogenes when compared to control clones. Afatinib resistant H1975 tumor clones expressed less PTEN than control clones and in afatinib resistant clones this correlated with increased basal SRC Y416, ERBB3 Y1289, AKT T308 and mTOR S2448 phosphorylation, decreased expression of ERBB1, ERBB2 and ERBB3 and increased total expression of c-MET, c-KIT and PDGFRβ. Afatinib resistant clones were selectively killed by knock down of [ERBB3 + c-MET + c-KIT] but not by the individual or doublet knock down combinations. The combination of the ERBB1/2/4 inhibitor afatinib with the SRC family inhibitor dasatinib killed afatinib resistant H1975 cells in a greater than additive fashion; other drugs used in combination with dasatinib such as sunitinib, crizotinib and amufatinib were less effective. [Afatinib + dasatinib] treatment profoundly inactivated ERBB3, AKT and mTOR in the H1975 afatinib resistant clones and increased ATG13 S318 phosphorylation. Knock down of ATG13, Beclin1 or eIF2α strong suppressed killing by [ERBB3 + c-MET + c-KIT] knock down, but were only modestly protective against [afatinib + dasatinib] lethality. Thus afatinib resistant H1975 NSCLC cells rely on ERBB1- and SRC-dependent hyper-activation of residual ERBB3 and elevated signaling, due to elevated protein expression, from wild type c-MET and c-KIT to remain alive. Inhibition of ERBB3 signaling via both blockade of SRC and ERBB1 results in tumor cell death.

Radiation Treatment in Women with Ovarian Cancer: Past, Present, and Future

Ovarian cancer is the most lethal of the gynecologic cancers, with 5-year survival rates less than 50%. Most women present with advanced stage disease as the pattern of spread is typically with dissemination of malignancy throughout the peritoneal cavity prior to development of any symptoms. Prior to the advent of platinum-based chemotherapy, radiotherapy was used as adjuvant therapy to sterilize micrometastatic disease. The evolution of radiotherapy is detailed in this review, which establishes radiotherapy as an effective therapy for women with micrometastatic disease in the peritoneal cavity after surgery, ovarian clear cell carcinoma, focal metastatic disease, and for palliation of advanced disease. However, with older techniques, the toxicity of whole abdominal radiotherapy and the advancement of systemic therapies have limited the use of radiotherapy in this disease. With newer radiotherapy techniques, including intensity-modulated radiotherapy (IMRT), stereotactic body radiotherapy (SBRT), and low-dose hyperfractionation in combination with targeted agents, radiotherapy could be reconsidered as part of the standard management for this deadly disease.

A randomized phase II evaluation of weekly gemcitabine plus pazopanib versus weekly gemictabine alone in the treatment of persistent or recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma

5532

Background: Inhibition of angiogenesis is a valuable treatment strategy for ovarian cancer. Pazopanib (paz) is a potent angiogenic small molecular inhibitor of the tyrosine kinases VEGRF-1, -2, -3, PDGFR, c-kit and has shown activity as a single agent in ovarian cancer. We designed a trial to assess the benefit of adding paz to gemcitabine (gem) in patients with recurrent, advanced ovarian cancer. Methods: An open-label, randomized, multi-site, phase 2 trial was conducted (NCT01610206) including patients with platinum resistant or sensitive ovarian cancer with up to 3 prior lines of chemotherapy, and measurable or evaluable disease. Patients were randomly assigned (1:1) to receive weekly gem 1000 mg/m2 with or without paz 800 mg QD and stratified according to platinum sensitivity and number of prior lines (1 vs 2 or 3). The primary endpoint was PFS. Intent-to-treat was defined as all eligible patients who receive any protocol treatment with analysis based on randomized arm. Results: As of 3/2017, we randomized 148 and treated 146 patients (target sample size 148 eligible patients who receive any protocol treatment). 75 (46 platinum resistant, 61%) were randomly assigned to receive gem/paz and 71 (41 platinum resistant, 58%) to receive gem only. 110 patients (75%) had received 2 or 3 prior lines. There were no unexpected toxicities or deaths. Adverse events were more common in the gem/paz group. The most common grade 3–4 AEs (gem/paz vs gem) were: neutropenia (25 [33%] vs 15 [21%]), fatigue (7 [10%] vs 1 [2%]), hypertension (11 [15%] vs 1 [1%]), elevated alanine aminotransferase (8 [11%] vs 0), thrombocytopenia (9 [12%] vs 12[3%]) and anemia (7 [9%] vs 2 [3%]). There were 2 GI perforations in the paz arm. Median time on therapy was 12 weeks (range 1-55 weeks). Of the 138 patients off study to date, 30 (22%) were for AE’s (23 on gem/paz arm). Conclusions: The gem/paz combination is tolerable in this population, with patients tolerating multiple cycles with manageable toxicity. Median follow-up and PFS data will be presented after 122 events (progression or death) have occurred per protocol (currently 117 events). Clinical trial information: NCT01610206.

Establishment and characterization of a platinum- and paclitaxel-resistant high grade serous ovarian carcinoma cell line

High grade serous ovarian cancer (HGSOC) patients have a high recurrence rate after surgery and adjuvant chemotherapy due to inherent or acquired drug resistance. Cell lines derived from HGSOC tumors that are resistant to chemotherapeutic agents represent useful pre-clinical models for drug discovery. Here, we describe establishment of a human ovarian carcinoma cell line, which we term WHIRC01, from a patient-derived mouse xenograft established from a chemorefractory HGSOC patient who did not respond to carboplatin and paclitaxel therapy. This newly derived cell line is platinum- and paclitaxel-resistant with cisplatin, carboplatin, and paclitaxel half-maximal lethal doses of 15, 130, and 20 µM, respectively. Molecular characterization of this cell line was performed using targeted DNA exome sequencing, transcriptomics (RNA-seq), and mass spectrometry-based proteomic analyses. Results from exomic sequencing revealed mutations in TP53 consistent with HGSOC. Transcriptomic and proteomic analyses of WHIRC01 showed high level of alpha-enolase and vimentin, which are associated with cell migration and epithelial-mesenchymal transition. WHIRC01 represents a chemorefractory human HGSOC cell line model with a comprehensive molecular profile to aid future investigations of drug resistance mechanisms and screening of chemotherapeutic agents.

[Pemetrexed + Sorafenib] lethality is increased by inhibition of ERBB1/2/3-PI3K-NFκB compensatory survival signaling

In the completed phase I trial NCT01450384 combining the anti-folate pemetrexed and the multi-kinase inhibitor sorafenib it was observed that 20 of 33 patients had prolonged stable disease or tumor regression, with one complete response and multiple partial responses. The pre-clinical studies in this manuscript were designed to determine whether [pemetrexed + sorafenib] -induced cell killing could be rationally enhanced by additional signaling modulators. Multiplex assays performed on tumor material that survived and re-grew after [pemetrexed + sorafenib] exposure showed increased phosphorylation of ERBB1 and of NFκB and IκB; with reduced IκB and elevated G-CSF and KC protein levels. Inhibition of JAK1/2 downstream of the G-CSF/KC receptors did not enhance [pemetrexed + sorafenib] lethality whereas inhibition of ERBB1/2/4 using kinase inhibitory agents or siRNA knock down of ERBB1/2/3 strongly promoted killing. Inhibition of ERBB1/2/4 blocked [pemetrexed + sorafenib] stimulated NFκB activation and SOD2 expression; and expression of IκB S32A S36A significantly enhanced [pemetrexed + sorafenib] lethality. Sorafenib inhibited HSP90 and HSP70 chaperone ATPase activities and reduced the interactions of chaperones with clients including c-MYC, CDC37 and MCL-1. In vivo, a 5 day transient exposure of established mammary tumors to lapatinib or vandetanib significantly enhanced the anti-tumor effect of [pemetrexed + sorafenib], without any apparent normal tissue toxicities. Identical data to that in breast cancer were obtained in NSCLC tumors using the ERBB1/2/4 inhibitor afatinib. Our data argue that the combination of pemetrexed, sorafenib and an ERBB1/2/4 inhibitor should be explored in a new phase I trial in solid tumor patients.

Ruxolitinib synergizes with DMF to kill via BIM+BAD-induced mitochondrial dysfunction and via reduced SOD2/TRX expression and ROS

We determined whether the myelofibrosis drug ruxolitinib, an inhibitor of Janus kinases 1/2 (JAK1 and JAK2), could interact with the multiple sclerosis drug dimethyl-fumarate (DMF) to kill tumor cells; studies used the in vivo active form of the drug, mono-methyl fumarate (MMF). Ruxolitinib interacted with MMF to kill brain, breast, lung and ovarian cancer cells, and enhanced the lethality of standard of care therapies such as paclitaxel and temozolomide. MMF also interacted with other FDA approved drugs to kill tumor cells including Celebrex® and Gilenya®. The combination of [ruxolitinib + MMF] inactivated ERK1/2, AKT, STAT3 and STAT5; reduced expression of MCL-1, BCL-XL, SOD2 and TRX; increased BIM expression; decreased BAD S112 S136 phosphorylation; and enhanced pro-caspase 3 cleavage. Expression of activated forms of STAT3, MEK1 or AKT each significantly reduced drug combination lethality; prevented BAD S112 S136 dephosphorylation and decreased BIM expression; and preserved TRX, SOD2, MCL-1 and BCL-XL expression. The drug combination increased the levels of reactive oxygen species in cells, and over-expression of TRX or SOD2 prevented drug combination tumor cell killing. Over-expression of BCL-XL or knock down of BAX, BIM, BAD or apoptosis inducing factor (AIF) protected tumor cells. The drug combination increased AIF : HSP70 co-localization in the cytosol but this event did not prevent AIF : eIF3A association in the nucleus.

Celecoxib enhances [sorafenib + sildenafil] lethality in cancer cells and reverts platinum chemotherapy resistance

The present studies sought to determine whether the lethality of the drug combination [sorafenib + sildenafil] could be enhanced by the anti-inflammatory agent celecoxib, using ovarian cancer and other tumor cell lines as models. Also, in a dose dependent fashion celecoxib enhanced [sorafenib + sildenafil] lethality in multiple ovarian cancer cell lines. In a dose dependent fashion celecoxib enhanced the ability of [sorafenib + sildenafil] to reduce expression of multiple chaperone proteins in parallel with lower levels of the drug efflux pumps ABCB1 and ABCG2. Over-expression of GRP78 and HSP27 maintained pump expression in the presence of drugs. Cell killing by the 3 drug combination was mediated by mitochondrial / caspase 9 -dependent apoptotic signaling and by RIP-1 / caspases 2 and 4 / AIF -dependent necroptotic signaling. Pre-treatment of intrinsically resistant primary ovarian cancer cells with [celecoxib + sorafenib + sildenafil] significantly enhanced tumor cell killing by a subsequent cisplatin exposure. Similar data were obtained in some cancer cell lines, but not all, using the related platinum containing drugs, oxaliplatin and carboplatin. As our prior publications have also validated in vivo the combinations of [celecoxib + sildenafil] and [sorafenib + sildenafil] as cytotoxic to multiple tumor cell types, combined with the present findings, we would argue that the combination of celecoxib/sorafenib/sildenafil should be explored in a new phase I trial in ovarian cancer.

A phase II evaluation of selumetinib (AZD6244, ARRY-142886), a selective MEK-1/2 inhibitor in the treatment of recurrent or persistent endometrial cancer: an NRG Oncology/Gynecologic Oncology Group study

BACKGROUND

Activation of the mitogen activated protein kinase pathway plays a pivotal role in cell proliferation and is frequently activated in endometrial cancer. We sought to evaluate the efficacy/safety of selumetinib, a selective MEK-1/2 inhibitor in women with recurrent endometrial cancer.

METHODS

This was a phase II, single-arm, open-label study evaluating response and 6-month event-free survival (EFS) as primary endpoints. Eligible patients had measurable disease, 1-2 prior cytotoxic regimens, and performance status 0-2. Selumetinib 75mg PO BID was administered daily until progression or intolerance. One cycle was 28days.

RESULTS

Fifty-four patients were enrolled; 2 were excluded due to improper pre-study treatment (1) and never treated (1), leaving 52 evaluable for efficacy/safety. Median age was 62; histology included endometrioid (58%), serous (17%) and mixed (23%). Seventeen patients (33%) had 2 prior cytotoxic regimens. The median number of cycles administered was 2 (1-34). Three (6%) patients had objective response (1 CR, 2 PR); 13 had SD as best response. The proportion of patients with 6-month EFS was 12%. Median EFS, progression-free and overall survival was 2.1, 2.3, and 8.5months, respectively. Drug-attributed grade 3/4 adverse events were observed (≥5%) were fatigue (15%), anemia (10%), pain (10%), extremity edema (8%), and dyspnea (6%). There was 1 grade 4 infection (renal), 1 grade 4 anemia, and 1 death due to hemorrhage (rectum).

CONCLUSIONS

Selumetinib was tolerable in this population but did not meet pre-trial specifications for clinical efficacy.

Elevated AKAP12 in paclitaxel-resistant serous ovarian cancer cells is prognostic and predictive of poor survival in patients

A majority of high-grade (HG) serous ovarian cancer (SOC) patients develop resistant disease despite high initial response rates to platinum/paclitaxel-based chemotherapy. We identified shed/secreted proteins in preclinical models of paclitaxel-resistant human HGSOC models and correlated these candidate proteins with patient outcomes using public data from HGSOC patients. Proteomic analyses of a HGSOC cell line secretome was compared to those from a syngeneic paclitaxel-resistant variant and from a line established from an intrinsically chemorefractory HGSOC patient. Associations between the identified candidate proteins and patient outcome were assessed in a discovery cohort of 545 patients and two validation cohorts totaling 795 independent SOC patients. Among the 81 differentially abundant proteins identified (q < 0.05) from paclitaxel-sensitive vs -resistant HGSOC cell secretomes, AKAP12 was verified to be elevated in all models of paclitaxel-resistant HGSOC. Furthermore, elevated AKAP12 transcript expression was associated with worse progression-free and overall survival. Associations with outcome were observed in three independent cohorts and remained significant after adjusted multivariate modeling. We further provide evidence to support that differential gene methylation status is associated with elevated expression of AKAP12 in taxol-resistant ovarian cancer cells and ovarian cancer patient subsets. Elevated expression and shedding/secretion of AKAP12 is characteristic of paclitaxel-resistant HGSOC cells, and elevated AKAP12 transcript expression is a poor prognostic and predictive marker for progression-free and overall survival in SOC patients.

A phase II study of ramucirumab (IMC-1121B) in the treatment of persistent or recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma

OBJECTIVE

Vascular endothelial growth factor (VEGF) receptor-mediated signaling contributes to ovarian cancer pathogenesis. Elevated VEGF expression is associated with poor clinical outcomes. We investigated ramucirumab, a fully human anti-VEGFR-2 antibody, in patients with persistent or recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma. Primary endpoints were progression-free survival at 6 months (PFS-6) and confirmed objective response rate (ORR).

METHODS

Women who received ≥ 1 platinum-based chemotherapeutic regimen and had a platinum-free interval of <12 months with measurable disease were eligible. Patients received 8 mg/kg ramucirumab intravenously every 2 weeks.

RESULTS

Sixty patients were treated; one patient remained on study as of September 2013. The median age was 62 years (range: 27-80), and median number of prior regimens was 3. Forty-five (75%) patients had platinum refractory/resistant disease. Thirty-nine patients (65.0%) had serous tumors. PFS-6 was 25.0% (n=15/60, 95% CI: 14.7-37.9%). Best overall response was: partial response 5.0% (n=3/60), stable disease 56.7% (n=34/60), and progressive disease 33.3% (n=20/60). The most common treatment-emergent adverse events possibly related to study drug were headache (65.0%; 10.0% Grade ≥ 3), fatigue (56.7%; 3.3% Grade ≥ 3), diarrhea (28.3%; 1.7% Grade ≥ 3), hypertension (25.0%; 3.3% Grade ≥ 3), and nausea (20.0%; no Grade ≥ 3). Two patients experienced intestinal perforations (3.3% Grade ≥ 3). Pharmacodynamic analyses revealed changes in several circulating VEGF proteins following initial ramucirumab infusion, including increased VEGF-A, PlGF and decreased sVEGFR-2.

CONCLUSIONS

Although antitumor activity was observed, the predetermined efficacy endpoints were not met.

Current approaches and challenges in managing and monitoring treatment response in ovarian cancer

Epithelial ovarian cancer is the leading cause of death among gynecologic malignancies. Treatment of recurrent ovarian cancer remains a challenge despite advances in surgical and chemotherapeutic options. A goal of many providers is to detect recurrences as early as possible and initiate treatment though there is controversy as to whether this impacts outcome. Elevations in CA125 and radiological findings may precede symptoms of recurrence by several months. While detection of recurrences by physical exam alone is unusual, a thorough exam in conjunction with reported symptoms and elevated CA125 is sufficient to detect 80-90% of recurrences. A spiral CT scan may be used to confirm recurrence in the setting of asymptomatic CA125 elevation and a PET/CT can yield additional insight if the CT is inconclusive. Initiating chemotherapy prior to the development of symptoms, even in the setting of elevated CA125, does not impact overall survival primarily because the efficacy of available treatments in the recurrent setting is poor. More information about tumor biology and ways to predict which patients will benefit from available treatment options is required. Consequently, the approach to post-treatment surveillance should be individualized taking into account the clinical benefit of the second-line therapy, versus the costs and morbidity of the surveillance method.

A phase II, open-label, multicenter study of IMC-1121B (ramucirumab; RAM) monotherapy in the treatment of persistent or recurrent epithelial ovarian (EOC), fallopian tube (FTC), or primary peritoneal (PPC) carcinoma (CP12-0711/NCT00721162)

5012

Background: VEGF receptor-mediated-signaling contributes to ovarian cancer pathogenesis. Elevated VEGF expression and serum levels are associated with poor clinical outcomes. We investigated RAM, a fully human VEGFR-2 antagonist antibody, in patients (pts) with persistent or recurrent EOC/FTC/PPC. Methods: Adult women with EOC/FTC/PPC who had completed ≥1 platinum (P)-based chemotherapeutic (ct) regimen and had a P-free interval (PFI) of <12 months (m), progression on, or persistent disease after P-based therapy were eligible. Any number of prior ct regimens was allowed. ECOG PS 0-1 and adequate organ function were required. Pts received 8 mg/kg RAM IV every 2 weeks. Primary endpoints were progression-free survival at 6m (PFS-6) and confirmed objective response rate (ORR) by RECIST 1.0. Results: 60 pts were treated; 1 remains on study as of Dec 2011. Median age was 62 years (range 27-80). Median number of prior regimens was 3 (range 1– 14). 51 pts (85%) received ≥ 2 prior regimens; 25 pts (42%) received >3 prior regimens. 45 pts (75%) were P resistant or refractory, with 65% (39 pts) serous tumors. PFS-6: 34.2% (95% CI: 21.7% – 47%). Best overall response: 3 PR (5%), 34 SD (57%), 20 PD (33%) and 3 not evaluable (5%). Median duration of PR: 5.6m (3.7, 5.6, 17.5); median PFS: 3.5m (95% CI: 2.3 – 5.3). Median OS: 11.1m (95% CI: 8.3 – 17.0). No unexpected toxicities were observed. Grade (G) 3 adverse events (AEs) observed in >5% of pts were: headache (10%) and fatigue (8%). No G4 AEs were observed in >5% of pts. 5 deaths occurred on RAM or within 30 days of discontinuation; 4 due to PD, and 1 due to intestinal perforation. 1 G4 bowel perforation and one G4 colo-vaginal fistula were noted. All 3 cases of perforation/fistula occurred in the setting of progressive, large-volume disease. Correlative biomarker studies are ongoing to identify patients most likely to benefit. Conclusions: Ramucirumab was reasonably tolerated and demonstrated single-agent activity in persistent or recurrent ovarian carcinoma, with approximately one-third of patients progression free at 6 months.

Randomized phase III trial of tamoxifen versus thalidomide in women with biochemical-recurrent-only epithelial ovarian, fallopian tube or primary peritoneal carcinoma after a complete response to first-line platinum/taxane chemotherapy with an evaluation of serum vascular endothelial growth factor (VEGF): A Gynecologic Oncology Group Study

PURPOSE

To compare progression-free survival (PFS), overall survival (OS) and toxicities of thalidomide versus tamoxifen and to evaluate serum vascular endothelial growth factor (VEGF) in biochemical-recurrent epithelial ovarian cancer, primary peritoneal cancer or fallopian tube carcinoma (EOC/PPC/FTC).

METHODS

Biochemical recurrence was defined as a rising CA-125 exceeding twice the upper limit of normal without evidence of disease as defined by RECIST 1.0 criteria. Women with FIGO stages III and IV, histologically confirmed EOC/PPC/FTC who were free of disease following first-line chemotherapy were randomized to oral thalidomide 200mg daily with escalation to a maximum of 400 mg or tamoxifen 20mg orally twice daily for up to 1 year, progression or adverse effect prohibited further treatment. VEGF was quantified by ELISA in pre and post-treatment serum.

RESULTS

Of the 139 women randomized, 138 were eligible. Interim analysis showed that thalidomide did not reduce the recurrence rate relative to tamoxifen, and the trial was closed. Thalidomide versus tamoxifen was associated with a similar risk of progression (HR = 1.31, 95% confidence interval [CI] = 0.93-1.85), an increased risk of death (HR = 1.76, 95% CI = 1.16-2.68) and more grades 3 and 4 toxicities (55% versus 3%). The most common grades 3 and 4 toxicities were constitutional (12%), somnolence (12%), pulmonary (9%), venous thromboembolism (VTE) (6%) and peripheral neurologic (6%) for thalidomide, with VTE (1.4%) and gastrointestinal (1.4%) for tamoxifen. Serum VEGF was not associated with clinical characteristics, treatment, PFS or OS.

CONCLUSION

Thalidomide was not more effective than tamoxifen in delaying recurrence or death but was more toxic. VEGF was not prognostic in this cohort.

CA-125 change after chemotherapy in prediction of treatment outcome among advanced mucinous and clear cell epithelial ovarian cancers: a Gynecologic Oncology Group study

BACKGROUND

There are limited data regarding unique clinical or laboratory features associated with advanced clear cell (CC) and mucinous (MU) epithelial ovarian cancers (EOC), particularly the relationship between CA-125 antigen levels and prognosis.

METHODS

A retrospective review of 7 previously reported Gynecologic Oncology Group phase 3 trials in patients with stage III/IV EOC was conducted. A variety of clinical parameters were examined, including the impact of baseline and changes in the CA-125 level after treatment of CC and MU EOC on progression-free (PFS) and overall survival (OS).

RESULTS

Clinical outcomes among patients with advanced CC and MU EOC were significantly worse when compared with other cell types (median PFS, 9.7 vs 7.0 vs 16.7 months, respectively, P < .001; median OS, 19.4 vs 11.3 vs 40.5 months, respectively, P < .001). Suboptimal debulking was associated with significantly decreased PFS and OS among both. Although baseline CA-125 values were lower in CC (median, 154 micron/mL) and MU (100 micron/mL), compared with other cell types (275 micron/mL), this level did not appear to influence outcome among these 2 specific subtypes of EOC. However, an elevated level of CA-125 at the end of chemotherapy was significantly associated with decreased PFS and OS (P < .01 for all).

CONCLUSIONS

Surgical debulking status is the most important variable at prechemotherapy predictive of prognosis among advanced CC and MU EOC patients. Changes in the CA-125 levels at the end treatment as compared with baseline can serve as valid indicators of PFS and OS, and likely the degree of inherent chemosensitivity.

The prognostic value of pretreatment CA 125 in patients with advanced ovarian carcinoma: a Gynecologic Oncology Group study

BACKGROUND

The objective of the current study was to determine the prognostic significance of a pretreatment serum CA 125 level in patients with advanced epithelial ovarian carcinoma (EOC) who received treatment with a standard chemotherapy regimen.

METHODS

Patients with International Federation of Gynecology and Obstetrics stage III/IV ovarian carcinoma who were on 1 of 7 Gynecologic Oncology Group (GOG) phase 3 trials and received treatment with a standard regimen of intravenous cisplatin and paclitaxel were included. A Cox regression model was used to assess the impact of CA 125 levels drawn before the initiation of chemotherapy on progression-free survival (PFS) both overall and by subgroup, including surgical debulking status, disease stage, and histologic subtype.

RESULTS

In total, 1,299 patients who were on the cisplatin/paclitaxel arms of the GOG trials were eligible. The median CA 125 level was 246 U/mL. Only 7.6% of patients had a normal CA 125 level (<or=35 U/mL). The lowest median CA 125 level was observed in the group with mucinous tumors; however, 69% of women who had mucinous tumors had abnormal CA 125 levels. Shorter PFS was observed with increasing CA 125 and persisted in multivariate analysis. Overall and in the serous subgroup, a 1-fold increase in CA 125 level was associated with a 7% increase in the hazard of disease progression (P < .001). This association was even more pronounced in patients who had stage III disease that was debulked to microscopic disease (15%; P = .003) and in patients who had endometrioid tumors (17%; P = .001).

CONCLUSIONS

A normal CA 125 level in the setting of advanced EOC was rare even after surgical debulking. The pretreatment CA 125 level was an independent predictor of PFS in patients with advanced EOC who received a standard chemotherapy regimen, particularly in the setting of disease that was debulked to a microscopic residual and in the serous or endometrioid subtypes.

Associations between ERBB2 amplification and progression-free survival and overall survival in advanced stage, suboptimally-resected epithelial ovarian cancers: a Gynecologic Oncology Group Study

OBJECTIVE(S)

The Gynecologic Oncology Group (GOG) examined the association between ERBB2 amplification and clinical covariates, tumor response, disease status post-chemotherapy, progression-free survival (PFS), and overall survival (OS) in epithelial ovarian cancer (EOC).

METHODS

Women with suboptimally-resected, advanced stage EOC who participated in GOG-111, a multi-center randomized phase III trial of cyclophosphamide+cisplatin versus paclitaxel+cisplatin, and provided a tumor block through the companion protocol GOG-9404 were eligible. ERBB2 amplification was examined using fluorescence in situ hybridization (FISH) with probes for ERBB2 and the centromere of chromosome 17 (CEP17).

RESULTS

ERBB2 amplification, defined as >2 copies of ERBB2/CEP17, was a rare event in EOC with 7% (9/133) of women exhibiting between 2.2 and 33.7 copies of ERBB2/CEP17, and was not associated with patient age, race, GOG performance status, stage, cell type, grade, measurable disease status, volume of ascites, tumor response or disease status post-chemotherapy. Women with >2 verses < or =2 copies of ERBB2/CEP17 did not have a reduced risk of disease progression (hazard ratio [HR]=0.56; 95% confidence interval [CI]=0.27-1.16; p=0.120) or death (HR=0.57; 95% CI=0.26-1.23; p=0.152), and ERBB2 amplification was not an independent prognostic factor for PFS or OS. ERBB2 amplification, defined as >4 copies of ERBB2/nuclei, was observed in 9% (12/133) of women with levels ranging from 4.2 to 49.2 copies of ERBB2/nuclei, and was associated with older age and volume of ascites, but not with the other clinical covariates or outcome.

CONCLUSION(S)

ERBB2 amplification is a rare event and has no predictive or prognostic value in suboptimally-resected, advanced stage EOC treated with platinum-based combination chemotherapy.

Evaluation of new platinum-based treatment regimens in advanced-stage ovarian cancer: a Phase III Trial of the Gynecologic Cancer Intergroup

PURPOSE

To determine if incorporation of an additional cytotoxic agent improves overall survival (OS) and progression-free survival (PFS) for women with advanced-stage epithelial ovarian carcinoma (EOC) and primary peritoneal carcinoma who receive carboplatin and paclitaxel.

PATIENTS AND METHODS

Women with stages III to IV disease were stratified by coordinating center, maximal diameter of residual tumor, and intent for interval cytoreduction and were then randomly assigned among five arms that incorporated gemcitabine, methoxypolyethylene glycosylated liposomal doxorubicin, or topotecan compared with carboplatin and paclitaxel. The primary end point was OS and was determined by pairwise comparison to the reference arm, with a 90% chance of detecting a true hazard ratio of 1.33 that limited type I error to 5% (two-tail) for the four comparisons.

RESULTS

Accrual exceeded 1,200 patients per year. An event-triggered interim analysis occurred after 272 events on the reference arm, and the study closed with 4,312 women enrolled. Arms were well balanced for demographic and prognostic factors, and 79% of patients completed eight cycles of therapy. There were no improvements in either PFS or OS associated with any experimental regimen. Survival analyses of groups defined by size of residual disease also failed to show experimental benefit in any subgroup.

CONCLUSION

Compared with standard paclitaxel and carboplatin, addition of a third cytotoxic agent provided no benefit in PFS or OS after optimal or suboptimal cytoreduction. Dual-stage, multiarm, phase III trials can efficiently evaluate multiple experimental regimens against a single reference arm. The development of new interventions beyond surgery and conventional platinum-based chemotherapy is required to additionally improve outcomes for women with advanced EOC.

Associations between p53 overexpression and multiple measures of clinical outcome in high-risk, early stage or suboptimally-resected, advanced stage epithelial ovarian cancers A Gynecologic Oncology Group study

OBJECTIVE

The Gynecologic Oncology Group (GOG) performed a detailed analysis of p53 overexpression in previously-untreated women with invasive early or advanced stage epithelial ovarian cancer (EOC).

METHODS

Women were eligible for the study if they provided a tumor block for translational research and participated in either GOG-157, a randomized phase III trial of three versus (vs.) six cycles of paclitaxel+carboplatin in high-risk, early stage EOC, or GOG-111, a randomized phase III trial of cyclophosphamide+cisplatin vs. paclitaxel+cisplatin in suboptimally-resected, advanced stage EOC. The N-terminal DO-7 p53 antibody was used to examine the expression of the major normal and mutant p53-isoforms. p53 overexpression was defined as >or=10% tumor cells exhibiting nuclear staining.

RESULTS

p53 was overexpressed in 51% (73/143) and 66% (90/136) of cases in the GOG-157 and GOG-111 cohorts, respectively. In the GOG-157 cohort, p53 overexpression was not associated with any clinical characteristics or overall survival (OS) but was associated with worse progression-free survival (PFS) (logrank test: p=0.013; unadjusted Cox modeling: p=0.015). In the GOG-111 cohort, p53 overexpression was associated with GOG performance status (p=0.018) and grade (p=0.003), but not with age, stage, cell type or with tumor response and disease status after primary chemotherapy, PFS or OS. Adjusted Cox regression modeling demonstrated that p53 overexpression was not an independent prognostic factor for PFS or OS in either cohort.

CONCLUSIONS

p53 overexpression assessed by DO-7 immunostaining is common in early and advanced stage EOC, but has limited prognostic value in women treated with surgical staging and platinum-based combination chemotherapy.

Intraperitoneal chemotherapy: standard of care for patients with minimal residual stage III ovarian cancer?

Epithelial ovarian cancer is the leading cause of death from gynecological cancer in most of the Western world, and long-term survival remains poor despite good initial response to systemic therapy after debulking surgery. Even after complete pathological response, the risk of recurrence in the first few years is substantial. The peritoneum is the predominant site of failure and the disease remains confined to the peritoneal cavity for much of its course. Efforts to improve clinical outcomes in this group of patients included investigation of intraperitoneal administration of active agents to expose the low-volume postoperative residual disease in the peritoneum to high concentrations of these drugs. In spite of three National Cancer Institute-sponsored randomized trials demonstrating clinical benefit with intraperitoneal therapy in patients with advanced ovarian cancer, the fact remains that it is not uniformly accepted by the gynecologic oncology community in the USA and is rarely used by clinicians in Europe. Intraperitoneal regimens are perceived to be too toxic for administration, although most of the toxicity is reversible. In this article we discuss the available evidence for intraperitoneal chemotherapy, challenges facing the gynecologic oncology community to make this modality more widely acceptable, the selection of patients most likely to tolerate intraperitoneal therapy and ongoing research in this field.

Tumor residual after surgical cytoreduction in prediction of clinical outcome in stage IV epithelial ovarian cancer: a Gynecologic Oncology Group Study

PURPOSE

To identify factors predictive of poor prognosis in a similarly treated population of women with stage IV epithelial ovarian cancer (EOC).

PATIENTS AND METHODS

A retrospective review of 360 patients with International Federation of Gynecology and Obstetrics stage IV EOC who underwent primary surgery followed by six cycles of intravenous platinum/paclitaxel was performed. A proportional hazards model was used to assess the association of potential prognostic factors with progression-free survival (PFS) and overall survival (OS).

RESULTS

The median PFS and OS for this group of stage IV ovarian cancer patients was 12 and 29 months, respectively. Multivariate regression analysis revealed that histology, malignant pleural effusion, intraparenchymal liver metastasis, and residual tumor size were significant prognostic variables. Whereas patients with microscopic residual disease had the best outcome, patients with 0.1 to 1.0 cm residual disease and patients with 1.1 to 5.0 cm residual disease had similar PFS and OS. Patients with a residual size more than 5 cm had a diminished PFS and OS when compared with all other groups. Median OS for microscopic, 0.1 to 5.0 cm, and more than 5.0 cm residual disease was 64, 30, and 19 months, respectively.

CONCLUSION

Patients with more than 5 cm residual disease have the shortest PFS and OS, whereas patients with 0.1 to 1.0 and 1.1 to 5.0 cm have similar outcome. These findings suggest that ultraradical cytoreductive procedures might be targeted for selected patients in whom microscopic residual disease is achievable. Patients with less than 5.0 cm of disease initially and significant disease and/or comorbidities precluding microscopic cytoreduction may be considered for alternative therapeutic options other than primary cytoreduction.

Prognostic factors for stage III epithelial ovarian cancer: a Gynecologic Oncology Group Study

PURPOSE

Conflicting results on prognostic factors for advanced epithelial ovarian cancer (EOC) have been reported because of small sample size and heterogeneity of study population. The purpose of this study was to identify factors predictive of poor prognosis in a similarly treated population of women with advanced EOC.

PATIENTS AND METHODS

A retrospective review of demographic, pathologic, treatment, and outcome data from 1,895 patients with International Federation of Gynecology and Obstetrics stage III EOC who had undergone primary surgery followed by six cycles of intravenous platinum/paclitaxel was conducted. A proportional hazards model was used to assess the association of prognostic factors with progression-free survival (PFS) and overall survival (OS).

RESULTS

Increasing age was associated with increased risks for disease progression (HR = 1.06; 95% CI, 1.02 to 1.11 for an increase every 10 years) and death (HR = 1.12; 95% CI, 1.06 to 1.18). Mucinous or clear-cell histology was associated with a worse PFS and OS compared with serous carcinomas. Patients with performance status (PS) 1 or 2 were at an increased risk for recurrence compared with PS 0 (HR = 1.12; 95% CI, 1.01 to 1.24). Compared with patients with microscopic residual disease, patients with 0.1 to 1.0 cm and > 1.0 cm residual disease had an increased risk of recurrence (HR = 1.96; 95% CI, 1.70 to 2.26; and HR = 2.36; 95% CI, 2.04 to 2.73, respectively) and death (HR = 2.11; 95% CI, 1.78 to 2.49; P < .001; and HR = 2.47; 95% CI, 2.09 to 2.92, respectively).

CONCLUSION

Age, PS, tumor histology, and residual tumor volume were independent predictors of prognosis in patients with stage III EOC. These data can be used to identify patients with poor prognosis and to design future tailored randomized clinical trials.

A phase II study of irofulven in women with recurrent and heavily pretreated ovarian cancer

OBJECTIVE

To determine the safety and efficacy of a novel illudin S derivative, irofulven (MGI-114), in patients with recurrent ovarian cancer who had received extensive prior chemotherapy.

METHODS

The trial was an open label phase II study. Patients initially enrolled in this study were treated every 14 days with a dose of 24 mg/m2. Unexpected retinal toxicity associated with this dose and schedule lead to modification of the dosing to 0.55 mg/kg on the same schedule with a maximum individual dose of 50 mg. Dose reductions were permitted based on both hematologic and non-hematologic toxicities.

RESULTS

Seventy-four women were accrued and stratified into two cohorts including 58 women with platinum-resistant disease and 16 with platinum-sensitive disease. Non-hematologic toxicities included nausea, vomiting, and fatigue. Thirty-one women had between one and six visual symptoms, most were Grade 1 and 2 in nature. The majority of visual toxicities resolved either during treatment or post-treatment with irofulven. There was one partial response in each cohort with 19 (33%) and 8 (50%) of women having stable disease in the platinum-resistant and platinum-sensitive cohorts, respectively.

CONCLUSIONS

Irofulven at 24 mg/m2 on every 14-day schedule is associated with significant retinal toxicity in this patient population. Dosing at 0.55 mg/kg has persistent retinal toxicity, yet demonstrated only limited anti-tumor activity in a population of women who had received extensive prior chemotherapy.

Recurrent ovarian cancer

Ovarian cancer is the most common cause of death from gynecologic malignancies in the United States. Although ovarian cancer is very responsive to multiple chemotherapeutic agents, with objective response rates of up to 80% with the standard platinum and taxane doublets, 75% of patients relapse within 2 years of primary therapy and become candidates for treatment of recurrent disease. Recurrent ovarian cancer is increasingly approached as a chronic disease that requires sequential therapy with available agents. Several issues remain controversial regarding the treatment of patients with recurrent ovarian cancer, including the timing of salvage therapy, choice of agents, and use of monotherapy versus combination regimens. Also, the role of the CA125 tumor marker in detection of recurrence and assessing response to therapy remains unresolved. In this article we address these issues with an emphasis on evidence from the available literature and also discuss the clinical trials that are currently underway to resolve these issues.