Consolidation for ovarian cancer in remission

A phase II randomized, double-blind trial of a polyvalent Vaccine-KLH conjugate (NSC 748933 IND# 14384) + OPT-821 versus OPT-821 in patients with epithelial ovarian, fallopian tube, or peritoneal cancer who are in second or third complete remission: An NRG Oncology/GOG study

OBJECTIVE

Early-phase data have demonstrated induction of antibody responses to a polyvalent vaccine conjugate (Globo-H, GM2, MUC1-TN, TF) with adjuvant OPT-821. We sought to determine if this combination decreases the hazard of progression or death compared to OPT-821 alone in patients with ovarian cancer in second/third clinical complete remission following chemotherapy. Secondary and translational objectives were overall survival (OS), safety, and immunogenicity.

METHODS

From 2010-2013, patients were randomized (1:1) to receive OPT-821±vaccine-KLH conjugate subcutaneously at weeks 1, 2, 3, 7, 11, and then every 12 weeks (total 11). Dose delay or reduction was not permitted. Patients were removed for pre-defined dose-limiting toxicity.

RESULTS

Of 171 patients randomized, 170 were treated. Most had disease of serous histology (85%), stage 3 disease at diagnosis (77%), and had received 2 prior regimens (68%). 32% received >6 treatment cycles [median 6, each arm (p = 0.33)]. 77% discontinued due to progression, 4% due to toxicity, and 1 due to myeloid dysplastic syndrome (MDS). Maximum toxicities included grade 4 MDS and depression/personality change (1 each, unlikely related), as well as grade 3 gastrointestinal disorders and others (n = 21, 4 related). Lesser adverse events were injection site reactions (82%) and fever (11%). Estimated HR for progression-free survival (PFS) of the vaccine + OPT-821 to OPT-821 arm was 0.98 (95% CI: 0.71-1.36). At a median follow-up of 60 months, median OS was 47 and 46 months, respectively.

CONCLUSIONS

Vaccine + OPT-821 compared to OPT-821 alone was modestly immunogenic and did not prolong PFS or OS. Multi-remission patients are a viable, well-defined population for exploring innovative consolidation and maintenance approaches.

TRIAL REGISTRATION

NCT00857545.

Proteases and their inhibitors as prognostic factors for high-grade serous ovarian cancer

Ovarian carcinoma is one of the most lethal malignancies, but only very few prognostic biomarkers are known. The degradome, comprising proteases, protease non-proteolytic homologues and inhibitors, have been involved in the prognosis of many cancer types, including ovarian carcinoma. The prognostic significance of the whole degradome family has not been specifically studied in high-grade serous ovarian cancer. A targeted DNA microarray known as the CLIP-CHIP microarray was used to identify potential prognostic factors in ten high-grade serous ovarian cancer women who had early recurrence (<1.6 years) or late/no recurrence after first line surgery and chemotherapy. In women with early recurrence, we identified seven upregulated genes (TMPRSS4, MASP1/3, SPC18, PSMB1, IGFBP2, CFI - encoding Complement Factor I - and MMP9) and one down-regulated gene (ADAM-10). Using immunohistochemistry, we evaluated the prognostic effect of these 8 candidate genes in an independent cohort of 112 high-grade serous ovarian cancer women. Outcomes were progression, defined according to CA-125 criteria, and death. Multivariate Cox proportional hazard regression models were done to estimate the associations between each protein and each outcome. High ADAM-10 expression (intensity of 2-3) was associated with a lower risk of progression (adjusted hazard ratio (HR): 0.51; 95% confidence interval (CI): 0.29-0.87). High complement factor I expression (intensity 2-3) was associated with a higher risk of progression (adjusted HR: 2.30, 95% CI: 1.17-4.53) and death (adjusted HR: 3.42; 95% CI: 1.72-6.79). Overall, we identified the prognostic value of two proteases, ADAM-10 and complement factor I, for high-grade serous ovarian cancer which could have clinical significance.

A Phase I Study of Unimolecular Pentavalent (Globo-H-GM2-sTn-TF-Tn) Immunization of Patients with Epithelial Ovarian, Fallopian Tube, or Peritoneal Cancer in First Remission

We conducted a phase I study in ovarian cancer patients to evaluate the safety and immunogenicity of a synthetic unimolecular pentavalent carbohydrate vaccine (Globo-H, GM2, sTn, TF, and Tn) supported on a peptide backbone, conjugated to keyhole limpet haemocyanin (KLH), and mixed with immunological adjuvant QS-21. Twenty-four advanced-stage, poor-risk, first-remission ovarian cancer patients were enrolled from January 2011–Septermber 2013. Three dose levels were planned (25, 50, 100 mcg) with three cohorts of six patients each, with an additional 6-patient expansion cohort at the MTD. ELISA serologic IgM and IgG responses for each antigen was defined as positive response if antibody titers were ≥1:80 over the respective patient’s pre-vaccination serum. The study would be considered positive if at least four of 12 patients treated at the MTD showed immune responses for at least three of the five antigens. Twenty-four patients (median age, 54 years [range, 36–68]) were included in the safety analysis. Histology was high-grade serous in 22 patients (92%); 18 had stage III and six stage IV disease. The vaccine was well-tolerated at all doses, with no DLTs. At the highest treated dose, IgG and/or IgM responses were recorded against ≥3 antigens in 9/12 patients (75%), ≥4 in 7/12 (58%), and 5 in 3/12 (25%). With a median follow-up of 19 months (range, 2–39), 20 patients (83%) recurred and six (25%) died. The unimolecular pentavalent vaccine construct was shown to be safe and immunogenic. Such a construct greatly simplifies regulatory requirements and manufacturing, facilitates scalability, and provides adaptability.

General overview of radioimmunotherapy of solid tumors

Radioimmunotherapy (RIT) represents an attractive tool for the treatment of local and/or diffuse tumors with radiation. In RIT, cytotoxic radionuclides are delivered by monoclonal antibodies that specifically target tumor-associated antigens or the tumor microenvironment. While RIT has been successfully employed for the treatment of lymphoma, mostly with radiolabeled antibodies against CD20 (Bexxar(®); Corixa Corp., WA, USA and Zevalin(®); Biogen Idec Inc., CA, USA and Schering AG, Berlin, Germany), its use in solid tumors is more challenging and, so far, few trials have progressed beyond Phase II. This review provides an update on antibody-radionuclide conjugates and their use in RIT. It also discusses possible optimization strategies to improve the clinical response by considering biological, radiobiological and physical features.

Identifying clinical improvement in consolidation single-arm phase 2 trials in patients with ovarian cancer in second or greater clinical remission

OBJECTIVE

Estimates of progression-free survival (PFS) from single-arm phase 2 consolidation/maintenance trials for recurrent ovarian cancer are usually interpreted in the context of historical controls. We illustrate how the duration of second-line therapy (SLT), the time on the investigational therapy (IT), and patient enrollment plan can affect efficacy measures from maintenance trials and might result in underpowered studies.

METHODS

Efficacy data from 3 published single-arm consolidation therapies in second remission in ovarian cancer were used for illustration. The studies were designed to show an increase in estimated median PFS from 9 to 13.5 months. We partitioned PFS as the sum of the duration of SLT, treatment-free interval, and duration of IT. We calculated the statistical power when IT is given concurrently with SLT or after SLT by varying the start of IT. We compared the sample sizes required when PFS includes the time on SLT versus PFS that starts after SLT at initiation of IT.

RESULTS

Required sample sizes varied with duration of SLT. If IT starts with initiation of SLT, only 34 patients are needed to provide 80% power to detect a 33% hazard reduction. In contrast, 104 patients are required for a single-arm study for 80% power, if IT begins 7.5 months after SLT initiation.

CONCLUSIONS

Designs of nonrandomized consolidation trials that aim to prolong PFS must consider the effect of the duration of SLT on the end point definition and on required sample size. If IT is given concurrently with SLT, and after SLT, then SLT duration must be restricted per protocol eligibility, so that a comparison with historical data from other single-arm phase 2 studies is unbiased. If IT is given after SLT, the duration of SLT should be taken into account in the design stage because it will affect statistical power and sample size.

Clinical radioimmunotherapy--the role of radiobiology

Conventional external-beam radiation therapy is dedicated to the treatment of localized disease, whereas radioimmunotherapy represents an innovative tool for the treatment of local or diffuse tumors. Radioimmunotherapy involves the administration of radiolabeled monoclonal antibodies that are directed specifically against tumor-associated antigens or against the tumor microenvironment. Although many tumor-associated antigens have been identified as possible targets for radioimmunotherapy of patients with hematological or solid tumors, clinical success has so far been achieved mostly with radiolabeled antibodies against CD20 ((131)I-tositumomab and (90)Y-ibritumomab tiuxetan) for the treatment of lymphoma. In this Review, we provide an update on the current challenges aimed to improve the efficacy of radioimmunotherapy and discuss the main radiobiological issues associated with clinical radioimmunotherapy.

Abagovomab: an anti-idiotypic CA-125 targeted immunotherapeutic agent for ovarian cancer

Ovarian cancer remains the leading cause of death due to gynecologic malignancies. Most patients present with advanced disease at the time of diagnosis. Although many have a good initial response to surgical debulking and platinum-based chemotherapy, relapse is common, with the eventual development of chemotherapy resistance. Innovative treatments are needed in the remission setting to prolong the disease-free interval or prevent recurrence. Abagovomab is a murine monoclonal anti-idiotypic antibody (molecular weight: 165-175 kDa) that functionally imitates the tumor-associated antigen, CA-125. It has been shown to be well tolerated and to induce a sustained immune response in initial Phase I and II clinical trials. An ongoing, double-blind, placebo-controlled, multicenter, Phase III trial (MIMOSA) completed its double-blind period in December 2010 and will compare abagovomab maintenance therapy to placebo, which will definitively determine the efficacy of this immunotherapeutic approach in patients with ovarian cancer.

Progranulin is a potential prognostic biomarker in advanced epithelial ovarian cancers

OBJECTIVE

There are few validated relapse prediction biomarkers for epithelial ovarian cancer (EOC). We have shown progranulin (PGRN) and secretory leukocyte protease inhibitor (SLPI) are up regulated, overexpressed survival factors in EOC. We hypothesized they would predict presence of occult EOC.

METHOD

PGRN, SLPI, and the known biomarker HE4 were measured in EOC patient plasma samples, prospectively collected every 3 months from initial remission until relapse. Clinical data and CA125 results were incorporated into statistical analyses. Exploratory Kaplan-Meier estimates, dividing markers at median values, evaluated association with progression-free survival (PFS) and overall survival (OS). Area-under-the-curve (AUC) statistics were computed from receiver operating characteristic (ROC) curves to evaluate discrimination ability. A Cox proportional hazards model assessed the association between PFS, OS, and biomarkers, adjusting for clinical prognostic factors.

RESULTS

Samples from 23 advanced stage EOC patients were evaluated. PGRN at 3 months was the only biomarker independently associated with PFS (P<0.0001) and OS (P<0.003). When used to predict progression by 18 months, sensitivity and specificity were 93% and 100%, respectively, with AUC=0.944. The Cox model hazard ratio for PFS, divided at 59 ng/ml by ROC analysis and adjusted for clinical factors, was 23.5 (95% CI: 2.49-220). Combinations with SLPI, HE4, and/or CA125 did not improve the model.

CONCLUSIONS

We report pilot data indicating a potential independent association of PGRN on EOC patient PFS and OS. A validation study will be required to confirm this finding and to inform whether PGRN warrants evaluation as a potential screening biomarker.

Consolidation strategies in ovarian cancer: observations for future clinical trials

PURPOSE.: To describe the characteristics of a series of study populations of ovarian cancer patients with identical eligibility criteria in second or subsequent clinical remission (cCR) and to propose endpoint benchmarks for future consolidation studies. PATIENTS AND METHODS.: The patient populations consisted of those (1) untreated (U; observed until progression; n=35, (2) receiving imatinib (G; n=32), (3) receiving goserelin and bicalutamide (A; n=32), and (4) receiving vaccine (V; n=68; total=167). The endpoint of the combined analysis was progression-free survival in second remission (PFS 2). Patient characteristics were compared by chi-square test, and factors predicting PFS 2 evaluated in multivariate Cox model. RESULTS.: Groups were comparable for age, stage, grade, and debulking. Multivariate model to predict PFS 2 duration included histology, stage, optimal debulking, PFS 1 duration, and the type of intervention. As a benchmark for future studies, the median PFS 2 of the combined population of G, A, and U (removing V which had the most impact in prolonging PFS 2, n=68) was 11.3 months (95% CI: 10.4-12.5 months). The percent of patients with PFS 2>PFS 1 was 14/90 (16%). At 12 months, 43% remain progression-free. CONCLUSION.: Preliminary benchmarks for efficacy endpoints are suggested for future consolidation trials of patients in cCR. However, the suggested strategies will require validation in randomized trials and larger data sets.

Neoadjuvant chemotherapy for locally advanced breast cancer

Preoperative systemic therapy is the standard of care in locally advanced breast cancer. In this setting, the intent of preoperative systemic therapy is to expand surgical options and to improve survival. Locally advanced and inflammatory breast cancer have different biological features, but they share the use of preoperative (primary, neoadjuvant) systemic therapy as the initial treatment of choice. The management of these patients necessitates involvement of a multidisciplinary team from the onset and during therapy. The eradication of invasive cancer from the breast and axillary lymph nodes, pathologic complete response, is a predictor of outcome associated with improved disease-free and overall survival. However, conventional chemotherapy regimens result in pathologic complete response in only a minority of patients. The management of patients with residual invasive disease after preoperative therapy is a common clinical problem for which additional research is necessary. The differential expression of genes and pathways in locally advanced and inflammatory breast cancer allows for the exploitation of targeted therapy, and early trials have shown exciting target and tumor effects. Much work remains, and future trials combining targeted and conventional therapies based on molecular subtypes and/or specific targets are needed if we hope to improve survival for patients with locally advanced breast cancer.

Consolidation Therapy in Ovarian Cancer: A Clinical Update

Objectives:

To evaluate current strategies under investigation for use as consolidation or maintenance treatment in patients with ovarian cancer.

Patients with epithelial ovarian cancer often enter a complete remission after primary treatment. Many relapse, unfortunately, but some can return to remission after additional treatment. Outcomes can be improved by applying effective consolidation or maintenance approaches to patients in a complete primary or subsequent remission.

Methods:

A selective review of the literature is undertaken to consider strategies that are being or will likely be evaluated in randomized trials while we assess whether consolidation or maintenance will have a place in the treatment of patients with ovarian cancer.

Results:

The application of extended standard cytotoxic agents has been generally disappointing, and no strategy applied in the first remission setting has prolonged overall survival.

Conclusions:

As treatment options move beyond classic chemotherapy to novel hormones, immune interventions, and biologic agents, the consolidation strategy is regaining interest. This is particularly attractive in that many of these agents have stable disease as best outcome, and this is most appropriate to evaluate in patients with minimal volume disease. A consideration of toxicity is paramount, and any strategy to be considered in an otherwise asymptomatic patient in remission must be well tolerated. In addition, patients in second or third complete remission are also being considered as an appropriate group in which to evaluate new agents. Numerous other phase 2 trials with novel agents not considered here are underway, and it is to be hoped that some will emerge as contenders for randomized trials. Participation in these trials remains a priority for patients who otherwise must pursue a difficult watch-and-wait strategy.

Management of women with newly diagnosed ovarian cancer

Ovarian cancer is the leading cause of death from gynecologic cancers in the United States. Initial management is reviewed here and is best provided by a multidisciplinary team, including a gynecologic oncologist and a medical oncologist. Typically these patients are first treated with aggressive surgical debulking, followed by chemotherapy. Exceptions to this strategy, including those for patients adequately treated with surgery alone and those better served by neoadjuvant chemotherapy (NAC), are discussed. The history and rationale of current chemotherapy regimens, both intravenous (IV) and intraperitoneal (IP), are reviewed. Given the chemo-sensitive nature of this disease, as well as the fact that it remains largely incurable in advanced stages, efforts continue to be made to improve initial therapy. This disease represents an excellent target for new drug development, and some of the newer agents in trials for ovarian cancer are discussed.

Prognostic factors for patients with stage IV epithelial ovarian cancer receiving intraperitoneal chemotherapy after second-look assessment: results of long-term follow-up

BACKGROUND

The aim was to determine the long-term outcome for patients with FIGO stage IV epithelial ovarian carcinoma (EOC) treated with intraperitoneal (IP) chemotherapy after second-look assessment.

METHODS

By using data from a retrospective cohort of 433 patients who received IP therapy after second-look assessment after primary surgery and initial systemic therapy for EOC between 1984 and 1998 at our institution, all FIGO stage IIIC and IV patients were identified. Standard statistical methods were used.

RESULTS

Overall, 297 patients met study criteria (246 stage IIIC; 51 stage IV). The median survival for patients with stage IV disease was 34 months compared with 42 months for patients with stage IIIC disease (P=.02). The only significant predictor of overall survival in patients with stage IV disease was the presence of gross residual disease at initiation of IP therapy (P=.027). When comparing stage IV patients with and without pleural effusions to all stage IIIC patients, there was a significant trend toward improved survival in the patients with pleural effusions only compared with other stage IV patients (P=.01).

CONCLUSIONS

Prolonged overall survival was observed in patients with no gross residual disease at the time of IP chemotherapy initiation. When compared with similarly treated stage IIIC patients, stage IV patients with malignant pleural effusions appear to have a better outcome than those with other sites of metastasis. Future prospective trials should evaluate the use of IP therapy for patients with stage IV EOC by virtue of malignant pleural effusions only who responded to initial systemic therapy.

Are three additional cycles of chemotherapy useful in patients with advanced-stage epithelial ovarian cancer after a complete response to six cycles of intravenous adjuvant paclitaxel and carboplatin?

Background

To evaluate the efficacy of three additional cycles of chemotherapy in patients with the International Federation of Gynecology and Obstetrics Stage III or IV, who achieved a complete response after six cycles of intravenous adjuvant paclitaxel/carboplatin after surgery.

Methods

The clinical data of 94 patients with complete response after six cycles of adjuvant paclitaxel/carboplatin after surgery between January 1997 and March 2007 were reviewed retrospectively. Three additional cycles using the same chemotherapy were administered to 57 patients as consolidation chemotherapy (Group 1). Thirty-seven patients without the additional cycles served as controls (Group 2). Disease-free survival (DFS) and overall survival (OS) were evaluated using the Kaplan–Meier method with the log-rank test. The importance of consolidation chemotherapy as a prognostic factor affecting survival was examined using the Cox's proportional hazard analysis. The incidence of chemotherapy-induced hematological toxicities was compared between the two groups using chi-square test.

Results

Median DFS and mean OS were not significantly different between the two groups (15 versus 22 months, P = 0.703; 69 versus 73 months, P = 0.891, respectively). Consolidation chemotherapy was not a prognostic factor of survival although optimal debulking surgery and lower value of serum CA-125 levels after six cycles of the chemotherapy were prognostic factors improving DFS (P < 0.01). Grade 3 or 4 leukopenia was more common in patients treated with consolidation chemotherapy than in those not treated (50.9 versus 21.6%, P = 0.004).

Conclusion

Consolidation chemotherapy using paclitaxel/carboplatin may be inefficient and relatively toxic to advanced-stage epithelial ovarian cancer patients with complete response to six cycles of the same chemotherapy after surgery.

Radiation therapy and biological compounds for consolidation therapy in advanced ovarian cancer

Consolidation therapy is used in order to maximize the benefit of first-line therapy and to improve the progression-free and overall survival of patients. In women with advanced epithelial ovarian cancer, tested maintenance and consolidation strategies following first-line chemotherapy include high-dose chemotherapy, radiation therapy, intraperitoneal radionuclides including those linked to an antibody, and biological and immunologic agents. This review focuses on the current understanding of the benefit of radiation therapy and biological agents used as consolidation in women with advanced ovarian cancer. Whole abdominal radiation has given promising results only in the subgroup of patients with pathologic complete response. However, this treatment modality is associated with considerable intestinal toxicity. Single treatment with intraperitoneal radionuclides, either alone (32P) or in combination with an antibody (90Y-muHMFG1) has not improved survival. Biological agents used for consolidation include, eg, alpha- and gamma-interferon, tanomastat, a matrix metalloprotease inhibitor and oregovomab, a murine antibody that targets CA125. Randomized trials with these agents have not demonstrated any significant improvement in the overall survival of ovarian cancer patients. Currently, two ongoing studies (GOG 218, ICON7) are examining the potential of bevacizumab in the maintenance therapy of advanced epithelial ovarian cancer. Evaluation of new agents is indicated in order to achieve long-term disease-free survival in these patients. Toxicity and ease of administration must be reflected against the benefits of therapy.

A phase II evaluation of goserelin and bicalutamide in patients with ovarian cancer in second or higher complete clinical disease remission

BACKGROUND

The current study was conducted to determine the effect of goserelin and bicalutamide on progression-free survival (PFS) in patients with epithelial ovarian cancer who were in second or greater complete disease remission.

METHODS

Patients received bicalutamide at a dose of 50 mg orally daily and goserelin at a dose of 3.6 mg subcutaneously every 4 weeks. CA 125 was obtained monthly, with computed tomography performed every 3 months. Correlative studies included serum luteinizing hormone, follicle-stimulating hormone, vascular endothelial growth factor, free testosterone, and androstenedione and the germline polymorphisms CYP19A1 and androgen receptor.

RESULTS

Between October of 2000 and October of 2002, 35 patients were enrolled. Three patients (9%) received therapy at the time of first disease remission and were removed from the study, and 1 patient (3%) was removed for liver function test abnormalities. The most frequent toxicities were grade 1 alkaline phosphatase (54%), fatigue (57%), and hot flashes (42%) based on the National Cancer Institute common toxicity scale, version 2.0. The PFS for patients receiving protocol therapy in second disease remission (21 patients) was 11.4 months (95% confidence interval [95% CI], 10.2-12.6 months). The PFS for patients receiving protocol therapy in third or fourth disease remission (11 patients) was 11.9 months (95% CI, 10.8-14.1 months). The percentage of patients remaining in second disease remission at given times are: 100% at 3 months, 100% at 6 months, 72% at 9 months, 47% at 12 months, 28% at 15 months, 22% at 18 months, 19% at 21 months, and 13% at 24 months. There were no associations noted between androgen receptor repeat number, genotype, allelotype, or haplotypes and PFS.

CONCLUSIONS

The use of goserelin and bicalutamide did not appear to prolong PFS in patients with epithelial ovarian cancer in second or greater complete disease remission. The number of patients in disease remission at given time points may serve as a clinical trial endpoint for future studies of consolidation therapy.

Pilot study of a heptavalent vaccine-keyhole limpet hemocyanin conjugate plus QS21 in patients with epithelial ovarian, fallopian tube, or peritoneal cancer

PURPOSE

To characterize the safety and immunogenicity of a heptavalent antigen-keyhole limpet hemocyanin (KLH) plus QS21 vaccine construct in patients with epithelial ovarian, fallopian tube, or peritoneal cancer in second or greater complete clinical remission.

EXPERIMENTAL DESIGN

Eleven patients in this pilot trial received a heptavalent vaccine s.c. containing GM2 (10 microg), Globo-H (10 microg), Lewis Y (10 microg), Tn(c) (3 microg), STn(c) (3 microg), TF(c) (3 microg), and Tn-MUC1 (3 microg) individually conjugated to KLH and mixed with adjuvant QS21(100 microg). Vaccinations were administered at weeks 1, 2, 3, 7, and 15. Periodic blood and urine samples were obtained to monitor safety (complete blood count, comprehensive panel, amylase, thyroid-stimulating hormone, and urinalysis) and antibody production (ELISA, fluorescence-activated cell sorting, and complement-dependent cytotoxicity).

RESULTS

Eleven patients were included in the safety analysis; 9 of 11 patients remained on study for at least 2 weeks past fourth vaccination and were included in the immunologic analysis (two withdrew, disease progression). The vaccine was well tolerated. Self-limited and mild fatigue (maximum grade 2 in two patients), fever, myalgia, and localized injection site reactions were most frequent. No clinically relevant hematologic abnormalities were noted. No clinical or laboratory evidence of autoimmunity was seen. Serologic responses by ELISA were largely IgM against each antigen with the exception of Tn-MUC1 where both IgM and IgG responses were induced. Antibody responses were generally undetectable before immunization. After immunization, median IgM titers were as follows: Tn-MUC1, 1:640 (IgG 1:80); Tn, 1:160; TF, 1:640; Globo-H, 1:40; and STn, 1:80. Only one response was seen against Lewis Y; two were against GM2. Eight of nine patients developed responses against at least three antigens. Antibody titers peaked at weeks 4 to 8 in all patients. Fluorescence-activated cell sorting and complement-dependent cytotoxicity analysis showed substantially increased reactivity against MCF7 cells in seven of nine patients, with some increase seen in all patients.

CONCLUSIONS

This heptavalent-KLH conjugate plus QS21 vaccine safely induced antibody responses against five of seven antigens. Investigation in an adequately powered efficacy trial is warranted.

Duration of second or greater complete clinical remission in ovarian cancer: exploring potential endpoints for clinical trials

OBJECTIVE

To explore benchmarks for future consolidation strategies, we evaluated a strictly defined (normal CA-125 and normal CT) second-complete-remission (CR) ovarian cancer population for 1) the median progression-free survival (PFS), 2) the frequency with which second remission exceeds first, and 3) the proportion of patients in remission at given time points.

METHODS

Retrospective sampling was carried out at Memorial Sloan-Kettering (10/1993-12/2000) and the Royal Marsden Hospital (1/1995-4/2003) for the following: histological confirmation and elevated CA-125 at diagnosis; primary surgery; first-and second-line platinum-based chemotherapy with CR; and no maintenance therapy.

RESULTS

In 35 patients 1) the duration of first PFS was 17.8 months (95% CI, 13.2-24.5 months) and second PFS was 10.8 months (95% CI, 9.6-12.2 months); 2) the number of patients with second response longer than first was 3/35 (9%); 3) the proportion of patients remaining in second complete remission was 100% (3 months), 100% (6 months), 83% (9 months), 34% (12 months), 23% (15 months) and 8.6% (18 months), respectively.

CONCLUSION

1) The median PFS from second complete remission is short. 2) A second response is rarely longer than the first even in this second CR population. 3) The number of patients with a second response longer than the first, or the proportion of patients remaining in complete remission at given time points could be evaluated as an outcome measure in future studies.

CA125 level as a predictor of progression-free survival and overall survival in ovarian cancer patients with surgically defined disease status prior to the initiation of intraperitoneal consolidation therapy

OBJECTIVES

Recent data suggest that differences in CA125 levels within the normal range may predict progression-free survival (PFS), but limited information is available regarding the value of these differences in predicting overall survival (OS) in patients with epithelial ovarian cancer. The objective of this study was to determine whether CA125 is an independent predictor of OS in patients with surgically defined disease status at the end of primary therapy prior to intraperitoneal (IP) consolidation chemotherapy. A secondary objective was to assess the relationship of CA125 level to PFS.

METHODS

Using data from a retrospective cohort of 433 patients who received intraperitoneal (IP) therapy following primary treatment for ovarian cancer between 1984 and 1998, we identified 241 patients with a complete clinical response and CA125 data at the time of second-look surgery prior to IP chemotherapy. Patient demographics and updated follow-up status were abstracted from medical records. Kaplan-Meier survival curves were compared using the log-rank test, and Cox regression models were used for multivariate analysis.

RESULTS

The majority of patients had advanced stage III or IV disease (n=201, 83%) and high-grade histology (n=163, 68%). Taxane was used as part of primary platinum-based therapy in 56% (n=134) of patients, and subsequent IP chemotherapy was platinum-based in 85% (n=206). When considered as a continuous variable, CA125 was a predictor of OS (P=0.029). Using the median CA125 level in our study group as a cut-off, OS was increased in patients with CA125 < or =12 U/ml (median 5.8 years) compared with >12 (3.7 years) (P=0.0027). CA125 level was an independent predictor of OS (HR: 1.410; 95% CI, 1.044, 1.904, P=0.0248) in a multivariate model that included stage (P=0.0166), grade (P=0.0001), and findings at second-look surgery (P=0.0003). CA125 level was also a predictor of clinical PFS (radiographic or CA125 elevation criteria alone) in a subset of 161 patients as a continuous variable (P=0.0036), and when divided at the median (< or = or >12; median 2.8 years vs. 1.7 years; P=0.0017).

CONCLUSIONS

In our study population, CA125 level at the end of primary therapy was a predictor of OS and PFS when considered as a continuous variable, or when divided at the median (< or = or >12 U/ml). Further prospective study is required to optimize clinically significant cut-off values within the normal range of CA125 levels for both OS and PFS endpoints.