Weekly topotecan for recurrent platinum resistant ovarian cancer

Efficacy of cisplatin combined with vinorelbine as second- or higher-line palliative chemotherapy in patients with advanced ovarian cancer

The aim of this study was to assess the therapeutic efficacy of a cisplatin and vinorelbine combination as second- or higher-line palliative chemotherapy in patients with advanced ovarian cancer. We retrospectively reviewed the medical records of patients with advanced ovarian cancer who were treated with cisplatin (60 mg/m2 on day 1) and vinorelbine (25 mg/m2 on days 1 and 8) every 3 weeks between January 2004 and March 2021. Treatment responses, progression-free survival (PFS), and overall survival (OS) were assessed; laboratory data were reviewed to determine toxicity. Thirty-two patients with advanced ovarian cancer were treated with a combination of vinorelbine and cisplatin. The objective response rate (ORR) was 18.8% and the disease control rate was 75.1%. The median PFS was 4.13 months (95% confidence interval [CI], 2.4-5.8 months). The median OS was 56.9 months (95% CI, 50.5-63.7 months). The ORR (42.9% vs 9.1%; P = .035) was higher in the platinum-sensitive group than in the platinum-resistant group. The median PFS tended to be longer in the platinum-sensitive group (5.3 vs 3.8 months; P = .339) and the median OS was significantly longer in the platinum-sensitive group than in the platinum-resistant group (69.6 vs 24 months; P < .001). All patients developed hematological toxicities, with 56% experiencing grade 3 to 4 neutropenia. Two (6.2%) patients developed febrile neutropenia, but no treatment-related death occurred. This combination therapy may be effective in patients with heavily treated advanced ovarian cancer, particularly in platinum-sensitive patients.

Newly developed dual topoisomerase inhibitor P8-D6 is highly active in ovarian cancer

Background:

Ovarian cancer (OvCa) constitutes a rare and highly aggressive malignancy and is one of the most lethal of all gynaecologic neoplasms. Due to chemotherapy resistance and treatment limitations because of side effects, OvCa is still not sufficiently treatable. Hence, new drugs for OvCa therapy such as P8-D6 with promising antitumour properties have a high clinical need. The benzo[c]phenanthridine P8-D6 is an effective inductor of apoptosis by acting as a dual topoisomerase I/II inhibitor.

Methods:

In the present study, the effectiveness of P8-D6 on OvCa was investigated in vitro. In various OvCa cell lines and ex vivo primary cells, the apoptosis induction compared with standard therapeutic agents was determined in two-dimensional monolayers. Expanded by three-dimensional and co-culture, the P8-D6 treated cells were examined for changes in cytotoxicity, apoptosis rate and membrane integrity via scanning electron microscopy (SEM). Likewise, the effects of P8-D6 on non-cancer human ovarian surface epithelial cells and primary human hepatocytes were determined.

Results:

This study shows a significant P8-D6-induced increase in apoptosis and cytotoxicity in OvCa cells which surpasses the efficacy of well-established drugs like cisplatin or the topoisomerase inhibitors etoposide and topotecan. Non-cancer cells were affected only slightly by P8-D6. Moreover, no hepatotoxic effect in in vitro studies was detected.

Conclusion:

P8-D6 is a strong and rapid inductor of apoptosis and might be a novel treatment option for OvCa therapy.

Combination ATR and PARP Inhibitor (CAPRI): A phase 2 study of ceralasertib plus olaparib in patients with recurrent, platinum-resistant epithelial ovarian cancer

OBJECTIVE

Platinum-resistant, high-grade serous ovarian cancer (HGSOC) has limited treatment options. Preclinical data suggest that poly(ADP-ribose) polymerase inhibitors (PARPi) and ataxia telangiectasia and Rad3-related kinase inhibitors (ATRi) are synergistic. CAPRI (NCT03462342) is an investigator-initiated study of olaparib plus ceralasertib in recurrent HGSOC. Herein, we present results from the platinum-resistant cohort.

METHODS

A Simon 2-stage design was utilized. Platinum-resistant HGSOC patients received ceralasertib 160 mg orally daily, days 1-7 and olaparib 300 mg orally twice daily, days 1-28 of a 28-day cycle until toxicity or progression. Primary endpoints were toxicity and efficacy including objective response rate (ORR) by RECIST. Secondary endpoint was progression-free survival (PFS). The null hypothesis (≤5% ORR) would be rejected if there were ≥ 1 responses in 12 patients.

RESULTS

Fourteen PARPi-naïve patients were evaluable for toxicity; 12 were evaluable for response. Three had BRCA1 mutations (1 germline, 2 somatic). Adverse events possibly related to treatment were primarily grade (G) 1/2. G3 toxicities included nausea (14.3%), fatigue (7.1%), anorexia (7.1%), and anemia (7.1%). No objective responses occurred. Best response was stable disease in 9 patients and progressive disease in three. Five patients had a ≥ 20% to <30% reduction in disease burden, including 3 with BRCA1 mutations. Three of 11 patients (27%; 2 with BRCA1 mutations) evaluable by Gynecologic Cancer Intergroup criteria had >50% CA-125 decline, including 2 with CA-125 normalization. Median PFS was 4.2 months overall (90% CI:3.5-8.2) and 8.2 months (3.6 months-not determined) for patients with BRCA1 mutations.

CONCLUSIONS

Olaparib plus ceralasertib is well-tolerated. No objective responses occurred, though a signal of activity was seen particularly in disease associated with BRCA1. Further evaluation of this combination should include alternate dosing strategies in genomically-selected populations.

Therapeutic potential of thymoquinone in combination therapy against cancer and cancer stem cells

The long-term success of standard anticancer monotherapeutic strategies has been hampered by intolerable side effects, resistance to treatment and cancer relapse. These monotherapeutic strategies shrink the tumor bulk but do not effectively eliminate the population of self-renewing cancer stem cells (CSCs) that are normally present within the tumor. These surviving CSCs develop mechanisms of resistance to treatment and refuel the tumor, thus causing cancer relapse. To ensure durable tumor control, research has moved away from adopting the monotreatment paradigm towards developing and using combination therapy. Combining different therapeutic modalities has demonstrated significant therapeutic outcomes by strengthening the anti-tumor potential of monotreatment against cancer and cancer stem cells, mitigating their toxic adverse effects, and ultimately overcoming resistance. Recently, there has been growing interest in combining natural products from different sources or with clinically used chemotherapeutics to further improve treatment efficacy and tolerability. Thymoquinone (TQ), the main bioactive constituent of Nigella sativa, has gained great attention in combination therapy research after demonstrating its low toxicity to normal cells and remarkable anticancer efficacy in extensive preclinical studies in addition to its ability to target chemoresistant CSCs. Here, we provide an overview of the therapeutic responses resulting from combining TQ with conventional therapeutic agents such as alkylating agents, antimetabolites and antimicrotubules as well as with topoisomerase inhibitors and non-coding RNA. We also review data on anticancer effects of TQ when combined with ionizing radiation and several natural products such as vitamin D3, melatonin and other compounds derived from Chinese medicinal plants. The focus of this review is on two outcomes of TQ combination therapy, namely eradicating CSCs and treating various types of cancers. In conclusion, the ability of TQ to potentiate the anticancer activity of many chemotherapeutic agents and sensitize cancer cells to radiotherapy makes it a promising molecule that could be used in combination therapy to overcome resistance to standard chemotherapeutic agents and reduce their associated toxicities.

Efficacy of cisplatin combined with topotecan in patients with advanced or recurrent ovarian cancer as second- or higher-line palliative chemotherapy

The aim of this study was to evaluate the outcomes of patients with advanced or recurrent ovarian cancer treated with cisplatin combined with topotecan as second- or higher-line palliative chemotherapy.We retrospectively reviewed the medical records of patients with advanced or recurrent ovarian cancer, who were treated with cisplatin (50 mg/m on day 1) and topotecan (0.75 mg/m on days 1-3). Treatment response, progression-free survival (PFS) and overall survival (OS) were analyzed, and laboratory data were reviewed to evaluate toxicities.Thirty one patients were treated with cisplatin and topotecan. The objective response rate (ORR) was 22.6%, and the disease control rate (DCR) was 61.3%. The median PFS was 3.7 months (95% confidence interval [CI], 2.3-5.2 months) and the median OS was 44.5 months (95% CI, 35.5-53.5 months). The ORR (33.3% vs. 0%; P = .012) was significantly better in the platinum-sensitive group compared to the platinum-resistant group. The median PFS was significantly longer in the platinum-sensitive group compared to the platinum-resistant group (7.7 vs 2.5 months; P < .001), and the median OS was also significantly longer in the platinum-sensitive group (46.6 vs 19.3 months; P < .001). Almost all of the patients reported some degree of hematological toxicity. A high rate of grade 3-4 neutropenia (87.1%) was observed. Grade 3-4 thrombocytopenia (41.9%) and febrile neutropenia (19.4%) were also seen.The results showed that cisplatin combined with topotecan, as second- or higher-line palliative chemotherapy for patients with advanced or recurrent ovarian cancer, might be effective, especially in the platinum-sensitive group. However, attention should be paid to the high hematological toxicity associated with this drug combination.

Management of recurrent ovarian cancer: when platinum-based regimens are not a therapeutic option

Ovarian cancer relapses have been traditionally classified according to the platinum-free interval, leading to an arbitrary categorization of possible scenarios and treatment options. Its relevance in assessing treatment strategies has been revised in the last several years, as the panorama is constantly changing in the era of personalized medicine and targeted therapies. Factors to be considered while defining the best management of recurrent disease, and, consequently, the available treatment alternatives are increasing. Platinum remains one of the milestones of ovarian cancer treatment, but for some patients it might not be an ideal choice for several reasons other than limited platinum sensitivity. This review aims to analyze the scenarios in which platinum is not considered suitable in the management of patients with recurrent ovarian cancer, and the currently available alternatives.

A brief review of the management of platinum-resistant-platinum-refractory ovarian cancer

Ovarian cancer, which ranks fifth in cancer deaths among women, is the most lethal gynecologic malignancy. Epithelial ovarian cancer (EOC) is the most common histologic type, with the 5-year survival for all stages estimated at 45.6%. This rate increases to more than 70% in the minority of patients who are diagnosed at an early stage, but declines to 35% in the vast majority of patients diagnosed at advanced stage. Recurrent EOC is incurable. Platinum sensitivity (or lack thereof) is a major determinant of prognosis. The current standard treatment is primary surgery followed by platinum-based chemotherapy. In recurrent platinum-resistant/platinum-refractory EOC, sequential single-agent salvage chemotherapy is superior to multiagent chemotherapy. Multiagent regimens increase toxicity without clear benefit; however, no preferred sequence of single agents is recommended. The impact of targeted therapies and immunotherapies on progression-free survival and overall survival, which remains dismal, is under active investigation. Currently, clinical trials offer the best hope for the development of a new treatment paradigm in this recalcitrant disease.

Weekly Paclitaxel Versus Three-Weekly Paclitaxel in Recurrent Platinum-Resistant Epithelial Ovarian and Peritoneal Cancers: A Phase III Study

INTRODUCTION

Treatment of recurrent platinum-resistant ovarian and peritoneal cancers represents a therapeutic challenge. The aim of this Phase III prospective study was to compare the survival benefits, objective response rate, and toxicities among patients treated by weekly paclitaxel with those who underwent three-weekly paclitaxel in recurrent platinum-resistant ovarian and peritoneal cancers.

METHOD

Patients with recurrent platinum-resistant ovarian and peritoneal cancer were allocated to receive either weekly paclitaxel (arm 1) at 80 m/m² or three-weekly paclitaxel (arm 2) at 175 mg/m².

RESULTS

Fifty-five patients were enrolled (30 arm 1, 25 arm 2). The mean age was 56.7 years, and the median performance status was 0 (Eastern Cooperative Oncology Group [ECOG]). For arms 1 and 2, the objective response rates were 27% and 16%, the median progression-free survival were 7 and 4.5 months, and the median overall survival were 15.5 and 12.5 months, respectively. Treatments also significantly improved the quality of life. Treatment was associated with mild toxicities, and while neuropathy was slightly higher for weekly paclitaxel over three-weekly paclitaxel, hematological toxicities were significantly lower for the former than the latter.

CONCLUSION

Paclitaxel rechallenge showed antitumor activity in recurrent platinum-resistant ovarian and peritoneal cancers. Weekly paclitaxel achieved better results than three-weekly paclitaxel in terms of survival benefits, quality of life, and toxicities.

A phase 1b study of trebananib in combination with pegylated liposomal doxorubicin or topotecan in women with recurrent platinum-resistant or partially platinum-sensitive ovarian cancer

OBJECTIVE

To examine the tolerability and antitumor activity of trebananib plus pegylated liposomal doxorubicin (PLD) or topotecan in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer.

METHODS

In this open-label phase 1b study, patients received trebananib 10 mg/kg or 15 mg/kg IV QW plus PLD 50 mg/m(2) (cohorts A1 and A3, respectively) or topotecan 4 mg/m(2) (cohorts B1 and B3, respectively). Endpoints were dose-limiting toxicity (DLT; primary); treatment-emergent adverse events (AEs), overall response rate, anti-trebananib antibodies, and pharmacokinetics (secondary).

RESULTS

103 patients were enrolled. One patient in A1 and B1 had DLTs. Across all cohorts, the most common AEs were nausea, fatigue, and peripheral edema. Across both trebananib plus PLD cohorts (A1/A3), grade 4 AEs were pulmonary embolism, disease progression, and anemia. Two patients had grade 5 intestinal perforation (n=1) and sudden death (n=1). Across both trebananib plus topotecan cohorts (B1/B3), grade 4 AEs were neutropenia, hypokalemia, decreased granulocyte count, chest pain, dyspnea, decreased neutrophil count, and pulmonary embolism. Two patients had grade 5 disease progression. One patient had grade 5 pleural effusion associated with progressive disease. Confirmed objective response rates were 36.0% (A1), 34.8% (A3), 16.7% (B1), and 0.0% (B3). Median progression-free survival duration (months) was 7.4 (A1), 7.1 (A3), 3.5 (B1), and 3.1 (B3), respectively. No drug-drug interactions were apparent.

CONCLUSIONS

Trebananib 10mg/kg and 15 mg/kg IV QW plus PLD or topotecan appear to have acceptable toxicity profiles in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer. Antitumor activity was evident across all cohorts.

Weekly Topotecan for Recurrent Ovarian, Fallopian Tube and Primary Peritoneal Carcinoma: Tolerability and Efficacy Study—The Israeli Experience

Objectives

The purpose of this study was to assess the clinical activity and toxicity of weekly topotecan in a large cohort of epithelial ovarian (EOC), primary peritoneal (PPC), and tubal cancer patients.

Methods

Records of patients with recurrent EOC, PPC, and tubal cancer who were treated with weekly topotecan (4.0 mg/m2 on days 1, 8, and 15 on a 28-day cycle) after failure of more than 1 prior regimen were retrospectively reviewed in 8 centers in Israel.

Results

Two hundred four patients were evaluated for efficacy and toxicity. Median age was 62 years (range, 27–89 years); 121 (59.3%) were platinum sensitive. Patients were exposed to a median of 2 previous lines (range, 1–9), and 48.5% received only 1 prior chemotherapy regimen. Median follow-up was 15.5 months (range, 2.5–112 months). Overall response rate was 26.5%, of which 11 patients (5.4%) had complete response, and 43 patients (21.1%) had partial response. Clinical benefit rate (complete response + partial response + stable disease) was 65.7%. Median progression-free survival was 4.0 months (95% confidence interval [CI], 3.5–4.5 months). There was no significant difference between platinum-sensitive and platinum-resistant patients regarding response rate or progression-free survival. Median overall survival from disease diagnosis was 45.0 months (95% CI, 40.04–49.6 months) and 16.0 months (95% CI, 12.3–19.7 months) from initiation of topotecan therapy. Overall survival was significantly different between patients with platinum-sensitive and platinum-resistant disease (19.9 vs 10.8 months, respectively, P = 0.003; 95% CI, 8.1–16.3 months). Multivariate analysis showed that only platinum sensitivity and topotecan line were associated with overall survival. Weekly topotecan was well tolerated—with only 16.7% of patients experiencing grade 3 to 4 hematologic toxicities. There were no other grade 4 toxicities, and only 6.9% grade 3 toxicities.

Conclusions

In this large cohort of recurrent EOC, PPC, and tubal cancer, weekly topotecan was well tolerated with good clinical benefit rate, comparable to previous studies.

Sorafenib in combination with weekly topotecan in recurrent ovarian cancer, a phase I/II study of the Hoosier Oncology Group

OBJECTIVE

This trial determined the efficacy and tolerability of sorafenib and weekly topotecan in patients with platinum-resistant ovarian cancer (OC) or primary peritoneal carcinomatosis (PPC).

METHODS

Primary endpoints were maximum tolerated dose of sorafenib with weekly topotecan (phase I) and response rate (phase II). Secondary endpoints were progression free survival (PFS), overall survival (OS), toxicity, and rate of clinical benefit. Eligibility included recurrent platinum-resistant OC or PPC, <3 prior regimens, normal end-organ function. 3+3 dose escalation was used for phase I, sorafenib being tested at 400mg and 800 mg orally daily. Topotecan dose was reduced from 4 mg/m(2) to 3.5mg/m(2) IV weekly. The phase II regimen was sorafenib 400mg daily and topotecan 3.5mg/m(2) weekly on days 1, 8, 15 of a 28 days cycle.

RESULTS

16 patients were enrolled in phase I and 14 patients in phase II. Median age was 52.5 years (range 35-79), 27 patients had OC, and 3 PPC. Median number of cycles administered was 2.5 (0-15). There were 5 partial responses (PR) (16.7%), and 14 patients (46.7%) with stable disease (SD). Four PRs were recorded during phase I and 1 during phase II. One of those PRs occurred in a patient with platinum-sensitive disease. Grade 3/4 toxicities included leukopenia/neutropenia (23%), thrombocytopenia (17%), anemia (10%), fatigue, nausea, vomiting (7% each). One case of grade 3 hand-foot syndrome was recorded.

CONCLUSIONS

The combination of sorafenib and topotecan causes significant toxicity, precluding administration of full doses and resulting in modest clinical efficacy in platinum resistant OC or PPC.

Recent progress in the diagnosis and treatment of ovarian cancer

Epithelial ovarian cancer is the most lethal of the gynecologic malignancies, largely due to the advanced stage at diagnosis in most patients. Screening strategies using ultrasound and the cancer antigen (CA) 125 tumor marker are currently under study and may lower stage at diagnosis but have not yet been shown to improve survival. Women who have inherited a deleterious mutation in the BRCA1 or BRCA2 gene and those with the Lynch syndrome (hereditary nonpolyposis colorectal cancer) have the highest risk of developing ovarian cancer but account for only approximately 10% of those with the disease. Other less common and less well-defined genetic syndromes may increase the risk of ovarian cancer, but their contribution to genetic risk is small. A clear etiology for sporadic ovarian cancer has not been identified, but risk is affected by reproductive and hormonal factors. Surgery has a unique role in ovarian cancer, as it is used not only for diagnosis and staging but also therapeutically, even in patients with widely disseminated, advanced disease. Ovarian cancer is highly sensitive to chemotherapy drugs, particularly the platinum agents, and most patients will attain a remission with initial treatment. Recent advances in the delivery of chemotherapy using the intraperitoneal route have further improved survival after initial therapy. Although the majority of ovarian cancer patients will respond to initial chemotherapy, most will ultimately develop disease recurrence. Chemotherapy for recurrent disease includes platinum-based, multiagent regimens for women whose disease recurs more than 6 to 12 months after the completion of initial therapy and sequential single agents for those whose disease recurs earlier. New targeted biologic agents, particularly those involved with the vascular endothelial growth factor pathway and those targeting the poly (ADP-ribose) polymerase (PARP) enzyme, hold great promise for improving the outcome of ovarian cancer.

Phase II trial of lapatinib and topotecan (LapTop) in patients with platinum-refractory/resistant ovarian and primary peritoneal carcinoma

OBJECTIVE

Resistance to chemotherapy is a major challenge in the treatment of ovarian/peritoneal cancer. One purported mechanism of topotecan resistance is the breast cancer resistance protein (BCRP) and P-glycoprotein (Pgp). We designed a phase II clinical trial evaluating the efficacy and adverse event profile of concomitant topotecan and lapatinib, a small molecule pan-erbB inhibitor that can block BCRP/Pgp efflux of topotecan.

METHODS

Patients with platinum-refractory or resistant epithelial ovarian/peritoneal cancer were treated with topotecan 3.2 mg/m² IV on Day 1, 8 and 15 and lapatinib 1250 mg PO daily, continuously in 28 day cycles. The primary endpoint was response rate. For correlative studies, archived tissue was assessed for expression of EGFR, HER2, HIF-1α, CD31, and BCRP.

RESULTS

Eighteen patients were enrolled and treated. Four experienced evidence of clinical benefit: one partial response and three with stable disease. Using a two-stage Simon design, the trial was stopped after the first stage due to insufficient activity. Grades 3+ and 4+ adverse events (AE) were experienced in 14 and 4 patients, respectively. The most common grade 3/4 AE were neutropenia (56%), thrombocytopenia (28%), and diarrhea (22%).

CONCLUSIONS

The combination of lapatinib plus topotecan for the treatment of platinum refractory/resistant epithelial ovarian cancer lacks sufficient activity to warrant further investigation. In particular, hematologic adverse events were substantial. Expression of correlative study markers did not reveal patterns of predicted benefit or toxicity. Disruption of erbB signaling and BCRP/Pgp efflux with lapatinib was insufficient for overcoming topotecan resistance, suggesting alternative mechanisms of resistance are involved.

Combined weekly topotecan and biweekly bevacizumab in women with platinum-resistant ovarian, peritoneal, or fallopian tube cancer: results of a phase 2 study

BACKGROUND

A phase 2 trial was conducted to determine the toxicity and efficacy of combined weekly topotecan and biweekly bevacizumab in patients with primary or secondary platinum-resistant ovarian, peritoneal, or fallopian tube cancer (OC).

METHODS

Patients were treated with bevacizumab 10 mg/kg on days 1 and 15 and topotecan 4 mg/m(2) on days 1, 8, and 15 of a 28-day cycle until progressive disease (PD) or excessive toxicity. The primary endpoint was progression-free survival (PFS); secondary objectives included overall survival (OS), objective response, and toxicity.

RESULTS

Patients (N = 40) received a median of 8 treatment cycles. Toxicity was generally mild or moderate, with neutropenia (18%), hypertension (20%), gastrointestinal toxicity (18%), pain (13%), metabolic toxicity (15%), bowel obstruction (10%), and cardiotoxicity (8%) being the most common grade 3 and 4 adverse events. No bowel perforations, febrile neutropenia, or treatment-related deaths occurred. Median PFS and OS were 7.8 (95% confidence interval [CI], 3.0-9.4) and 16.6 months (95% CI, 12.8-22.9), with 22 (55%) patients progression-free for ≥6 months. Ten (25%) patients had partial response (PR), 14 (35%) had stable disease (SD), and 16 (40%) had PD. Patients treated with 2 prior regimens received greater benefit than patients treated with 1: PR/SD, 78.9% versus 42.9% (P = .03); median PFS, 10.9 versus 2.8 months (P = .08); median OS, 22.9 versus 12.8 months (P = .02).

CONCLUSIONS

A weekly topotecan and biweekly bevacizumab combination demonstrates acceptable toxicity and encouraging efficacy in patients with platinum-resistant OC; further study is warranted.

A phase II study of two topotecan regimens evaluated in recurrent platinum-sensitive ovarian, fallopian tube or primary peritoneal cancer: a Gynecologic Oncology Group Study (GOG 146Q)

OBJECTIVE

To evaluate the efficacy and safety of topotecan in patients with recurrent ovarian, primary peritoneal, and fallopian tube carcinomas.

METHODS

A randomized phase II analysis of platinum-sensitive patients with measurable disease was performed independently assessing intravenous topotecan 1.25 mg/m2 daily×5 every 21 days (regimen I) and topotecan 4.0 mg/m2/day on days 1, 8, and 15 of a 28-day cycle (regimen II). All patients were treated until disease progression, unmanageable toxicity, or patient refusal. Insufficient accrual related to regimen I resulted in a redesign of the study as a single arm phase II trial assessing only regimen II. More complete efficacy data is presented for regimen II as enrollment on regimen I was insufficient for some analyses.

RESULTS

A total of 81 patients were enrolled. One patient was ineligible. Fifteen patients received regimen I, while 65 patients were treated with regimen II. The response rate on regimen I (daily×5) was 27% (90% CI: 10-51%) and 12% (90% CI: 6-21%) on regimen II (weekly). The median PFS and OS were 4.8 and 27.8 months, respectively, for regimen II. Grade 3/4 neutropenia rate was 93% with daily×5 dosing and 28% for weekly treatment. Febrile neutropenia was very low in both groups.

CONCLUSION

The weekly regimen of topotecan appeared less active but resulted in less toxicity than the daily regimen in platinum-sensitive recurrent ovarian cancer patients.

Topotecan Weekly Versus Conventional 5-Day Schedule in Patients With Platinum-Resistant Ovarian Cancer: a randomized multicenter phase II trial of the North-Eastern German Society of Gynecological Oncology Ovarian Cancer Study Group

PURPOSE

Weekly administration of topotecan (Tw) is less toxic and widely considered a better treatment option than conventional 5-day therapy (Tc) in women with platinum-resistant recurrent ovarian cancer. We conducted a randomized phase II trial (TOWER [Topotecan Weekly Versus Conventional 5-Day Schedule in Patients With Platinum-Resistant Ovarian Cancer]) to better define the ratio between benefits and risks with either treatment approach.

PATIENTS AND METHODS

Patients were randomly assigned to two independent two-stage protocols of Tw (4 mg/m(2)/wk administered on days 1, 8, and 15) or Tc (1.25 mg/m(2)/d on days 1 to 5). We evaluated risk ratios (RRs) for the primary end point of clinical benefit (complete response, partial response, and stable disease), the duration of progression-free survival (PFS) and overall survival (OS), associated hazard ratios (HRs), and RRs of toxicity with 95% CIs.

RESULTS

In total, 194 patients were randomly assigned at 54 centers to Tw (n = 97) or Tc (n = 97). Clinical benefit was observed in 36 of 76 (47%; 95% CI, 36% to 59%) Tw and 46 of 80 (58%; 95% CI, 46% to 68%) Tc patients (RR, 1.21; 95% CI, 0.90 to 1.64; P = .205). Patients in the Tw group had a slightly shorter PFS (HR, 1.29; 95% CI, 0.96 to 1.76) but similar OS (HR, 1.04; 95% CI, 0.74 to 1.45) compared with Tc. Tw was associated with significantly lower risks of anemia (RR, 0.35; 95% CI, 0.16 to 0.79), neutropenia (RR, 0.38; 95% CI, 0.23 to 0.65), and thrombocytopenia (RR, 0.23; 95% CI, 0.09 to 0.57).

CONCLUSION

With regard to effectiveness in terms of response and PFS, Tc remains the standard of care in patients with platinum-resistant recurrent ovarian cancer. However, comparable OS rates and a favorable toxicity profile make Tw another viable treatment option in this setting.

Overcoming platinum resistance in ovarian carcinoma

IMPORTANCE OF THE FIELD

Ovarian cancer remains a deadly malignancy because most patients develop recurrent disease that is resistant to chemotherapy, including platinum. Because response rates for current treatment regimens are relatively similar and unfortunately low, no standard chemotherapy for platinum-resistant ovarian cancer exists.

AREAS COVERED IN THIS REVIEW

A systematic literature review of clinical studies published between January 2005 and March 2010 was conducted using search engines, PubMed and MEDLINE with the entry keywords 'ovarian cancer' and 'platinum resistance'. This search revealed 40 clinical trials (1793 patients).

WHAT THE READER WILL GAIN

Gemcitabine was the most common drug used in clinical trials reporting higher response rates, ≥ +1 SD of overall response rate (5 out of 8). Gemcitabine-based combination therapy showed an average response rate of 27.2% (95% CI, 22.4-32.0). Combination of gemcitabine and pegylated liposomal doxorubicin (PLD) was the most common regimen (n = 3) and was associated with possible additive effects in platinum-resistant ovarian cancer patients: response rate, gemcitabine alone 6.1%, PLD alone 19.8%, and gemcitabine with PLD 28.7% (95% CI, 20.4-37.0), respectively.

TAKE HOME MESSAGE

Analysis of recent clinical trials showed that gemcitabine-based combination chemotherapy was associated with the highest antitumor effects in platinum-resistant ovarian cancer patients during the study period.

Phase I and pharmacologic study of weekly bolus topotecan for advanced non-small-cell lung cancer

PURPOSE

We conducted a phase I trial of the topoisomerase I inhibitor topotecan for the purpose of determining the maximum tolerated dose (MTD) and the dose-limiting toxicities (DLTs) of topotecan when administered weekly to patients with advanced non-small-cell lung cancer.

PATIENTS AND METHODS

Twelve patients with stage IIIB or IV disease were treated with topotecan by 30-minute intravenous infusion on days 1, 8, and 15 every 4 weeks. The dose was escalated in 2-mg/m2 increments from the starting dose of 4 mg/m2 until the MTD was reached. After the MTD had been reached in previously treated patients, chemotherapy-naive patients were enrolled for treatment at that dose, and the dose was escalated to estimate the MTD in the treatment-naive group.

RESULTS

The MTD of topotecan was determined to be 6 mg/m2 in the previously treated group and 8 mg/m2 in the chemotherapy-naive group. All 3 previously treated patients experienced DLT at the 6-mg/m2 dose level. Although only 1 of the 3 previously treated patients experienced DLT (grade 4 neutropenia for > or = 3 days) at the 8-mg/m2 dose level, skipping the topotecan dose on day 15 because of neutropenia was reported in 2 patients. Anorexia and general fatigue were the common nonhematologic toxicities.

CONCLUSION

The recommended dose of topotecan for phase II studies in previously untreated patients is 6 mg/m2 on days 1, 8, and 15, every 28 days, and 4 mg/m2 appears to be a suitable dose for use in previously treated patients with this schedule.

Phase I trial of liposomal doxorubicin and ZD1839 in patients with refractory gynecological malignancies or metastatic breast cancer

BACKGROUND

Pegylated liposomal doxorubicin has activity in both breast and ovarian cancer. Preclinical data noted that ZD1839 acts synergistically with chemotherapy. Given the lack of cross-resistance between these two agents, a phase I trial was initiated examining the safety and efficacy of the combination of liposomal doxorubicin and ZD1839 in patients with recurrent gynecologic or metastatic breast cancer.

METHODS

Dose-limiting toxicity (DLT) was defined within the first two cycles of treatment. Escalating doses of liposomal doxorubicin were administered every 4 weeks with ZD1839. Pharmacokinetic analysis and correlative studies were performed.

RESULTS

Thirty-five patients were enrolled in this study: six in each cohort. One DLT (febrile neutropenia) was observed in cohort 2. Dose level 3 was determined to be the maximum tolerated dose (MTD), and an additional ten patients were accrued. Serious adverse events (SAEs) included one patient with mental status changes believed secondary to disease progression and two central nervous system (CNS) bleeds believed to be unrelated to the combination of study agents. Toxicities were generally mild except for skin and gastrointestinal toxicity. No cardiac toxicity was observed. The best response to therapy included four partial responses and 20 patients with stable disease.

CONCLUSIONS

Liposomal doxorubicin with ZD1839 is an active regimen but is associated with increased skin toxicity in patients with advanced breast and gynecologic cancer.

Review role of topotecan in gynaecological cancers: current indications and perspectives

BACKGROUND

Ovarian cancer is the fourth cause of death from gynaecological cancer and cervical cancer is the first in women <45 years old in developing countries. The aim of this article is to review the role of topotecan (Hycamtin), a semi-synthetic alkaloid derivative of camptothecin, in ovarian and cervical cancer in monotherapy and in combination.

METHODS

This article reviews the mechanism of action, pharmacokinetics, toxicity and efficacy of topotecan. The paper also reports the principal phases II and III studies of topotecan in advanced or recurrent ovarian and cervical cancer.

RESULTS

Topotecan (Hycamtin), currently indicated for the treatment of relapsed ovarian cancer, has demonstrated activity both in platinum-sensitive and in platinum-resistant disease. The combination cisplatin-topotecan for the treatment of advanced and recurrent cervical cancer has demonstrated a clinical benefit in terms of response rate, overall survival and progression free survival. Haematological toxicity of topotecan also is easy to manage and not cumulative, especially with the weekly scheduled recently introduced in clinical practice.

CONCLUSION

Topotecan (Hycamtin) will continue to play a role in the treatment of advanced ovarian and cervical cancer, in monotherapy or in combination with other cytotoxic agents.

A phase II study of weekly topotecan and docetaxel in heavily treated patients with recurrent uterine and ovarian cancers

OBJECTIVES

A phase II trial designed to evaluate the safety and efficacy of weekly topotecan and docetaxel in heavily treated patients with recurrent uterine or epithelial ovarian cancers.

METHODS

Eligible patients with recurrent epithelial ovarian or uterine cancers were treated with weekly topotecan 3.5 mg/m(2) and docetaxel 30 mg/m(2) for 3 consecutive weeks. Cycles were repeated every 4 weeks for 6 cycles or until evidence of disease progression, unacceptable toxicity, or death. Response was assessed as per RECIST or Rustin's criteria. Time to best response and overall survival were calculated using Kaplan-Meier statistical methods.

RESULTS

Twenty-seven patients registered, of which 24 were evaluable for response. The majority of patients had received 2 prior chemotherapy regimens. Of the total 86 cycles of chemotherapy that were administered, there were three grade 4 (all neutropenia) and ten grade 3 toxicities. Six of the grade 3 non-hematologic toxicities were unrelated to treatment. There were 8 dose delays and 4 dose reductions. The overall response rate was 25% (95% CI: 7.7%-42.3%, 8% CR, 17% PR), and 38% of the patients had clinical benefit (95% CI: 18.1%-56.9%; CR+PR+13% SD). The median duration of response was 8.5 months (range 3-19 months). The median overall survival was 18.5 months (range 1.8-50.7 months).

CONCLUSION

The combination of weekly topotecan and docetaxel has clinical benefit and is well tolerated in this heavily treated patient population. Patients with platinum-resistant tumors had clinical benefit and should be considered for further study with this regimen.

Current role and future aspects of topotecan in relapsed ovarian cancer

BACKGROUND

Ovarian cancer is the fifth leading cause of cancer deaths in women. It is associated with a poor prognosis, as the majority of patients present with advanced disease and relapse after radical surgery, and following chemotherapy with carboplatin and paclitaxel.

OBJECTIVE

To review the role of topotecan in the treatment of advanced and relapsed ovarian cancer, and the efficacy and safety of novel dosing regimens and formulations of topotecan. It will also discuss further options of combination of topotecan with other cytotoxic agents and targeted therapies.

RESEARCH DESIGN AND METHODS

The authors searched for relevant references in the MEDLINE database and in congress abstracts of the American Society of Clinical Oncology.

RESULTS

Topotecan is an established second-line therapy for advanced and relapsed ovarian cancer; a regimen of 1.5 mg/m(2)/day 1-5 has been approved in the USA and many other western countries. Topotecan is well tolerated; associated haematological toxicity is generally manageable, reversible and non-cumulative. A number of alternative dosing regimens and formulations have been investigated in an attempt to improve the toxicity profile of topotecan without compromising anti-tumour activity. A novel oral formulation of topotecan has shown clinical promise in patients with advanced and relapsed disease. Administration of i.v. topotecan on a weekly basis produced encouraging results in several phase II trials, with less haematological toxicity and similar response rates to the day 1-5 regimen. Also, recent early studies demonstrate that topotecan is effective in combination with several other therapeutic agents in the relapsed setting.

CONCLUSION

The peer-reviewed literature reports that topotecan is an effective, well tolerated treatment option for relapsed ovarian cancer.