Rechallenge of immune checkpoint inhibitors in advanced non-small cell lung cancer

Immune checkpoint inhibitor (ICI) rechallenge in non-small cell lung cancer (NSCLC) is a promising therapeutic strategy. The situation for ICI rechallenge can be divided into three categories: adverse events (AEs); resistance to ICIs, and rechallenge becomes compulsive because of tumor relapse while the patients had completed a 2 year course of immunotherapy. However, these categories are still controversial and should be explored further. Through voting at the 6th Straits Summit Forum on Lung Cancer, in this study we summarize the consensus of 147 experts in ICI rechallenges. A total of 97.74% experts agreed to rechallenge; 48.87% experts rechallenge with the original drug, and the others rechallenge with a different drug; 40.3% agreed to rechallenge directly after progression; 88.06% experts agreed to ICI rechallenge with a combination regimen; and factors such as previous performance status score, PD-1 expression, and age should also be considered. Understanding the the clinical studies in ICI rechallenge could bring us one step closer to understanding the consensus. In patients with advanced NSCLC who have suffered recurrent or distant metastasis after immunotherapy, the option of rechallenge with ICIs is a promising treatment option.

Re-challenge of immune checkpoint inhibitor pembrolizumab with concurrent tocilizumab after prior grade 3 pneumonitis

Immune checkpoint inhibitors (ICIs) are associated with specific immune-related adverse events (irAEs) which are unique compared to cytotoxic chemotherapy. For life-threatening adverse events including grade 3 or more, permanent discontinuation of the ICIs is recommended, albeit without much robust evidence. Safe re-challenge of ICIs with concurrent immunosuppression has been reported with irAEs like gastrointestinal toxicity and arthritis. Here we present a case of a lady with undifferentiated pleomorphic sarcoma with programmed death ligand1 expression, who showed a complete response to pembrolizumab used as third-line therapy. However, it had to be stopped after 22 doses when the patient developed grade 3 pneumonitis. In view of progression off pembrolizumab, and lack of other effective alternatives, pembrolizumab was re-challenged with concurrent interleukin-6 (IL-6) blockade using tocilizumab. This was based on preliminary evidence on the role of IL-6 in mediating the irAEs, especially pneumonitis. The patient re-attained a complete response with pembrolizumab. There was no recurrence of the pneumonitis after rechallenging, and there was partial radiographic resolution of the ICI-interstitial lung disease after the combination therapy.

Second to none: rationale, timing, and clinical management of clozapine use in schizophrenia

Despite its enduring relevance as the single most effective and important evidence-based treatment for schizophrenia, underutilization of clozapine remains considerable. To a substantial degree, this is attributable to a reluctance of psychiatrists to offer clozapine due to its relatively large side-effect burden and the complexity of its use. This underscores the necessity for continued education regarding both the vital nature and the intricacies of clozapine treatment. This narrative review summarizes all clinically relevant areas of evidence, which support clozapine's wide-ranging superior efficacy - for treatment-resistant schizophrenia (TRS) and beyond - and make its safe use eminently feasible. Converging evidence indicates that TRS constitutes a distinct albeit heterogeneous subgroup of schizophrenias primarily responsive to clozapine. Most importantly, the predominantly early onset of treatment resistance and the considerable decline in response rates associated with its delayed initiation make clozapine an essential treatment option throughout the course of illness, beginning with the first psychotic episode. To maximize patients' benefits, systematic early recognition efforts based on stringent use of TRS criteria, a timely offer of clozapine, thorough side-effect screening and management as well as consistent use of therapeutic drug monitoring and established augmentation strategies for suboptimal responders are crucial. To minimize permanent all-cause discontinuation, re-challenges after neutropenia or myocarditis should be considered. Owing to clozapine's unique efficacy, comorbid conditions including substance use and most somatic disorders should not dissuade but rather encourage clinicians to consider clozapine. Moreover, treatment decisions need to be informed by the late onset of clozapine's full effects, which for reduced suicidality and mortality rates may not even be readily apparent. Overall, the singular extent of its efficacy combined with the high level of patient satisfaction continues to distinguish clozapine from all other available antipsychotics.

Long-term survival in extensive-stage small-cell lung cancer treated with different immune checkpoint inhibitors in multiple-line therapies: A case report and literature review

Background

Extensive-stage small-cell lung cancer (ES-SCLC) is highly malignant, is highly prone to recurrence, and has a short survival period. It is very difficult to achieve long-term survival in ES-SCLC, which has not been significantly improved in the last 20 years. For a long time, platinum-based chemotherapy has occupied the core position in the treatment of small-cell lung cancer (SCLC), but there are few options for treatment drugs or regimens, and if disease progression occurs, the options for follow-up regimens are obviously limited. The advent of immunotherapy has changed this situation to some extent, and immunotherapy has shown some effects in improving efficiency and prolonging survival, whether in first- or third-line therapy, but it is still unsatisfactory.

Case presentation

A 57-year-old patient with ES-SCLC experienced disease progression after four lines of treatment including synchronous radiotherapy, chemotherapy, and antiangiogenesis. However, the patient still benefited when switching to the programmed cell death receptor-1 (PD-1) inhibitor toripalimab in combination with chemotherapy in the fifth line. Even after the development of immune resistance, the patient still benefited after switching to tislelizumab in combination with different chemotherapy regimens or alone in the sixth and seventh lines. Following the progression of tislelizumab in combination with chemotherapy, the patient again profited after switching to durvalumab in combination with anlotinib and again achieved a progressive-free survival (PFS) of 11 months. Overall, the patient achieved a total of 45 months of PFS and 50 months of overall survival (OS), with a shocking and exciting 30 months of PFS achieved in the immune combination phase alone.

Conclusion

We report a patient with ES-SCLC who achieved long-term survival after at least eight lines of therapy including chemotherapy, antiangiogenesis, and different immune checkpoint inhibitors (ICIs). This suggests that long-term survival in SCLC is possible with aggressive, combined, and standardized treatment. Otherwise, immunotherapy postline enablement can still benefit patients, rechallenge after immune resistance is also possible in SCLC, and combination with chemotherapy or antiangiogenic therapy can improve the efficacy and prolong the survival. This will provide new ideas and options for the selection of treatment options for SCLC.

Pulmonary lesions following inoculation with the SARS-CoV-2 Omicron BA.1 (B.1.1.529) variant in Syrian golden hamsters

AbstractThe Omicron BA.1 (B.1.1.529) SARS-CoV-2 variant is characterized by a high number of mutations in the viral genome, associated with immune-escape and increased viral spread. It remains unclear whether milder COVID-19 disease progression observed after infection with Omicron BA.1 in humans is due to reduced pathogenicity of the virus or due to pre-existing immunity from vaccination or previous infection. Here, we inoculated hamsters with Omicron BA.1 to evaluate pathogenicity and kinetics of viral shedding, compared to Delta (B.1.617.2) and to animals re-challenged with Omicron BA.1 after previous SARS-CoV-2 614G infection. Omicron BA.1 infected animals showed reduced clinical signs, pathological changes, and viral shedding, compared to Delta-infected animals, but still showed gross- and histopathological evidence of pneumonia. Pre-existing immunity reduced viral shedding and protected against pneumonia. Our data indicate that the observed decrease of disease severity is in part due to intrinsic properties of the Omicron BA.1 variant.

Changes in Neutrophil to Lymphocyte Ratio, Lymphocyte to Monocyte Ratio, and Platelet to Lymphocyte Ratio During Palliative Radiotherapy May Predict Efficacy of Immune Checkpoint Inhibitor as Re-Challenge Treatment in Advanced Gastric Cancer: A Case Report

Introduction

Immunotherapy with programmed death-1 (PD-1) inhibitors has emerged as frontline option in patients with advanced or metastatic gastric cancer. However, two-thirds of patients who received PD-1 inhibitors treatment still had disease progression in 1 year. Subsequent treatment strategies as salvage options always lead to limited efficacy.

Case Description

Herein, we presented a case of recurrent metastatic gastric adenocarcinoma that had progressed on first-line treatment with nivolumab, in which systematic inflammation parameters with neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR), and platelet to lymphocyte ratio (PLR) were significantly changed by palliative radiotherapy on metastatic lymph nodes. The patient achieved persistent response to the re-challenge of immune checkpoint inhibitor, which resulted in survival time reaching 52 months, and is still in extension.

Conclusions

We supposed that the palliative radiotherapy may lead to the correction of NLR, LMR, and PLR and finally contribute to the efficacy of the re-challenge treatment by PD-1 inhibitor.

The Price of Success: Immune-Related Adverse Events from Immunotherapy in Lung Cancer

Cancer immunotherapy has the goal of enhancing a patient’s intrinsic immune processes in order to mount a successful immune response against tumor cells. Cancer cells actively employ tactics to evade, delay, alter, or attenuate the anti-tumor immune response. Immune checkpoint inhibitors (ICIs) modulate endogenous regulatory immune mechanisms to enhance immune system activation, and have become the mainstay of therapy in many cancer types. This activation occurs broadly and as a result, activation is supraphysiologic and relatively non-specific, which can lead to immune-related adverse events (irAEs), the frequency of which depends on the patient, the cancer type, and the specific ICI antibody. Careful assessment of patients for irAEs through history taking, physical exam, and routine laboratory assessments are key to identifying irAEs at early stages, when they can potentially be managed more easily and before progressing to higher grades or more serious effects. Generally, most patients with low grade irAEs are eligible for re-challenge with ICIs, and the use of corticosteroids to address an irAE is not associated with poorer patient outcomes. This paper reviews immune checkpoint inhibitors (ICIs) including their mechanisms of action, usage, associated irAEs, and their management.

Clinical characteristics and management of immune checkpoint inhibitor-related pneumonitis: A single-institution retrospective study

INTRODUCTION

The increasing application of immune checkpoint inhibitors (ICIs) will cause more checkpoint inhibitor-related pneumonitis (CIP), which is a common cause of ICI-related death. The clinical management of CIP needs further optimization.

METHODS

Patients who were managed at Peking Union Medical College Hospital (PUMCH) between February 2017 and December 2019 with a diagnosis of CIP were retrospectively analyzed. Clinical data including clinical manifestations, radiologic data, laboratory and bronchoscopy results, treatments, and outcomes were collected and analyzed. The Mann-Whitney test was used to compare patients with and without co-infections.

RESULTS

In total, 48 CIP cases in 42 patients were analyzed. The median time from the first dose of ICI to the onset of CIP was 1.9 months (range: 0.1-13.7). Grade 3-4 (G3-4) accounted for 30 cases (71.4%). The most common symptoms were cough (88.1%) and dyspnea (78.6%). The median starting dose of equivalent prednisone (EP) was 55 mg (range: 30-200) for all patients. The median total duration of glucocorticosteroids (GCS) treatment was 42.5 days (range: 15-89). Three patients (7.14%) died because of infection. A higher starting dose and longer duration of GCS (≥30 mg/day; p = 0.001) were associated with opportunistic infection. Chest computed tomography (CT) showed diverse and asymmetrical lesions. Twelve patients were re-challenged, and six patients developed recurrent CIP.

CONCLUSIONS

The clinical and imaging manifestations of CIP are various, and differential diagnosis of exclusion is essential. GCS at 1-2 mg/kg is feasible to treat CIP, but the duration of GCS ≥30 mg/day should be used with caution, given the high risk of acquired infections. Re-challenges of ICI are feasible, but the recurrence of CIP needs to be closely monitored.

Re-challenge of Platinum-based Chemotherapy for Platinum-refractory Patients with Recurrent or Metastatic Head and Neck Cancer: Claims Data Analysis in Japan

BACKGROUND

The role of platinum rechallenge in head and neck cancer (HNC) has not yet been fully evaluated.

OBJECTIVES

It is our goal to assess the real-world treatment patterns and usefulness of platinum rechallenge in patients with platinum-refractory recurrent or metastatic HNC receiving platinum rechallenge.

METHODS

This is a retrospective study using data from a Japanese hospital claims database stored in electronic hospital information systems. Patients with HNC or undefined histology with an HNC diagnosis using the disease code, between January 1, 2013 and September 30, 2016, were included. Patients diagnosed with other malignancies on or before the initial diagnosis of HNC and those without cancer stage information in the database were excluded from the study.

RESULTS

A total of 43 994 patients were identified from the database as HNC patients. Of those, in patients who had cancer progression within 6 months after platinum-based chemotherapy administered for primary or recurrent disease (N=842), the median treatment duration of platinum rechallenge for platinum refractory patients was only 1 cycle. The second-line treatment continuation rate at 6 months was 20.1% for patients who received platinum rechallenges and 32.8% for those who received non-platinum-based regimens.

CONCLUSIONS

The findings from this study of data from routine clinical practice suggest that the benefit of platinum rechallenge in a platinum-refractory setting would be limited.

Trabectedin Drug Holiday and Rechallenge in Soft Tissue Sarcomas: Report of 4 Cases and Literature Review

Soft tissue sarcomas are rare neoplasms, with a high mortality rate. Few drugs are available for the treatment of patients affected by metastatic sarcomas, who still have a 5-years survival rate lower than 20%. However, some of the more recent therapies can obtain long lasting responses in a portion of patients, such as Trabectedin. We analyzed four such cases treated at our Institute after progression to an anthracycline based regimen. In each case a therapeutic pause was proposed after at least 6 months of therapy with Trabectedin and in three out of four patients a re-challenge was proposed at progression, achieving again disease control or response. In two cases oligo-progressive sites were treated with localized therapies as stereotactic radiotherapy, delaying the systemic treatment re-start. In this article the reports of the patients involved are presented with a concise review of the relevant literature. Our findings support the favorable safety profile of Trabectedin and the feasibility of drug holidays, which should be at least discussed with the patient.

Rapid effect of osimertinib re-challenge on brain metastases developing during salvage cytotoxic chemotherapy after osimertinib treatment failure: A case report

We herein report a case of symptomatic brain metastases (BM) from lung adenocarcinoma in a 73-year-old female patient, which developed during salvage cytotoxic chemotherapy following failure of osimertinib treatment. The patient was proven to have a T790M mutation prior to osimertinib therapy, and achieved a clinical benefit from osimertinib for 3 years until the primary tumor progressed. Although active BM were not detected prior to initiating salvage cytotoxic chemotherapy, the patient developed numbness of the left hand, severe dizziness, and disturbance of behavior and thought after the 3-month course of the salvage cytotoxic chemotherapy. Brain magnetic resonance imaging revealed multiple BM with severe peritumoral brain edema. To avoid radiation-induced cognitive impairment, osimertinib re-challenge was undertaken. At 2 weeks after osimertinib initiation, the patient's neurological symptoms drastically improved. One month later, radiological evaluation revealed apparent shrinkage of the BM and subsiding brain edema, although the primary lung tumor remained stable. Therefore, osimertinib re-challenge may be a viable treatment option for BM developing during salvage cytotoxic chemotherapy.

Gemcitabine Re-challenge in Metastatic Soft Tissue Sarcomas: A Therapeutic Option for Selected Patients

BACKGROUND/AIM

Treatment options for patients with metastatic soft tissue sarcomas are limited. Re-challenge with a previously successful gemcitabine-based regimen is common. There are no published data to support this practice.

PATIENTS AND METHODS

We conducted a retrospective search to identify patients re-challenged with gemcitabine-based chemotherapy (GBC) from 2003 to 2015.

RESULTS

Twenty-nine patients re-challenged with gemcitabine were identified. The response rate for initial GBC was 55% (n=15) and for re-challenge GBC 26% (n=6). The median progression-free survival was 11.1 months (95%CI=7.2-11.9) for initial GBC and 5.3 months (95%CI=2.0-7.5) for re-challenge GBC. Overall survival following gemcitabine re-challenge was 12.2 months (95%CI=7.0-18.2). Twelve out of 26 evaluable patients (46%) treated with re-challenge GBC experienced grade 3-4 adverse events (CTCAE 4.03) with 31% (n=8) of patients requiring dose reduction.

CONCLUSION

In selected patients, gemcitabine re-challenge can be considered in advanced sarcomas, however, this approach is associated with toxicity.

Interest to consider re-challenging by cetuximab and platinum containing regimen in recurrent Head and Neck Cancer

Background

The EXTREME protocol is the standard of care for recurrent or metastatic head and neck squamous-cell carcinoma (R/M HNSCC) in first line. Beyond the first-line except immunotherapy, poor efficacy was reported by second-line chemotherapy. Re-challenge strategies based on a repetition of the first line with platinum and cetuximab regimens might have been an option to consider.

Methods

We performed a retrospective study in order to assess the efficacy of the cetuximab plus platinum doublet-based chemotherapy regimen in patients with R/M HNSCC progressing after at least 3 months of cetuximab maintenance (EXTREME protocol). We complete a retrospective review of all medical records from R/M HNSCC patients treated after 16 weeks with the EXTREME regimen and treated with a re-challenge strategy between January 2010 and December 2014 in our institution (Centre Paul Strauss, Strasbourg, France).

Results

33 patients were identified. The re-challenged strategy provided an ORR in 33.3% of cases and a DCR of 69.6% of cases. The median OS and PFS observed from the second line were 11.2 months and 6.5 months for the subset re-challenged by EXTREME or PCC regimens respectively. The response rate between patients with a platin free interval within 3 and 6 months and greater than 6 months were equal. Drugs dose intensity were better with the PCC protocol than the EXTREME regimen used as a rechallenge.

Conclusions

This study suggest re-challenging strategy by these regimens could be considered beyond the first line as an option when the platin free interval is greater than 3 months.

The efficacy of re-challenge with BRAF inhibitors after previous progression to BRAF inhibitors in melanoma: A retrospective multicenter study

BRAF and MEK inhibition is efficient in patients with BRAF V600-mutated metastatic melanoma, but due to acquired resistance the duration of response (DoR) is often only short-lived. In this retrospective multicenter study with 60 patients suffering from inoperable or metastatic melanoma we evaluated the efficacy of re-challenge with a BRAF inhibitor (BRAF2) with or without MEK-inhibition after progressive disease upon previous treatment with a BRAF inhibitor (BRAF1) with or without MEK inhibition.

Treatment with BRAF1 led to a disease control rate (DCR) of 90% with 12% complete responses (CR), 58% partial responses (PR) and 20% stable diseases (SD), the median progression-free survival (PFS) was 9.9 and DoR 10.7 months. BRAF2 with (68%) or without (32%) additional MEK inhibition was initiated after a median interval of 3.4 months. DCR after re-challenge with BRAF2 was 57%, 8% CR, 20% PR and 28% SD, median PFS was 5.0 and DoR 14.0 months. The duration of the treatment interval or the treatment in the interval did not influence the DCR or PFS to BRAF2. The only predictive factor for response to BRAF2 was previous response to BRAF1; all patients with CR to BRAF1 achieved disease control with BRAF2, but only 60% of the patients with PR to BRAF1 (p=0.002). Addition of MEK inhibition to BRAF2 after treatment with BRAF1 as monotherapy did not significantly increase the DCR or PFS compared to patients treated solely with mono- or combination therapy.

In conclusion re-challenge with a BRAF inhibitor is a meaningful therapeutic option for patients with BRAF V600-mutated metastatic melanoma.

Immune checkpoint inhibitor re-challenge in patients with advanced non-small cell lung cancer

Background

Immune checkpoint inhibitors have dramatically changed lung cancer treatment, demonstrating an overall survival benefit. There are limited data about re-challenge in patients with non-small cell lung cancer. We attempted to address this question for re-challenge of immune checkpoint inhibitor in patients with advanced non-small cell lung cancer.

Methods

We retrospectively analyzed 11 patients with advanced non-small cell lung cancer treated with nivolumab and re-challenged with nivolumab/pemblorizumab at Kansai Medical University Hospital from December 2015 to December 2017.

Results

Three patients achieved PR and two patients were in SD. These patients were apt to be good responders to the initial treatment, to develop immune-related adverse events and to be immediately started on re-challenge with immune checkpoint inhibitor. The median PFS was 2.7 (range, 0.5–16.1) months. Five patients (45%) had mild to moderate immune-related adverse events.

Conclusion

Our study shows the effectiveness of re-challenge of immune checkpoint inhibitors in a subset of non-small cell lung cancer patients. Re-challenge might become one of treatment option for advanced non-small cell lung cancer.

Cetuximab retreatment in patients with metastatic colorectal cancer who exhibited a clinical benefit in response to prior cetuximab: A retrospective study

Clinical benefits of cetuximab retreatment in patients with metastatic colorectal (mCRC) have been reported. In the present study, the effect of cetuximab retreatment on predictive markers was investigated by evaluating the clinical benefit of initial cetuximab treatment prior to cetuximab retreatment. Between November 2012 and March 2017, 14 patients with KRAS proto-oncogene GTPase exon 2 wild-type mCRC who exhibited a clinical benefit (confirmed stable disease for at least 6 months or a clinical response) to an initial cetuximab-based regimen, who received multiple lines of chemotherapy following disease progression and ultimately received a second cetuximab and irinotecan regimen, were retrospectively analyzed. For retreatment, patients received bi-weekly irinotecan (120-150 mg/m²) combined with cetuximab (400 mg/m² as an initial dose, followed by 250 mg/m², weekly). The median age of the 14 patients (11 males, 3 females) was 68 years (32-77). The median progression-free survival (PFS) following prior cetuximab-based therapy was 6.6 months (range, 4.1-18.4). Initial cetuximab treatment was administered as a first-line treatment in 11 patients, a second-line treatment in 1 patient and a third-line treatment in 2 patients. The median interval time between the last cycle of initial cetuximab-based therapy and the first cycle of cetuximab retreatment was 13.1 months (range, 6.0-37.1). The objective response rate of cetuximab retreatment was 21.4% and the median PFS was 4.4 months (95% confidence interval, 1.4-5.6). The Spearman's correlation coefficient for the PFS following retreatment and duration of initial cetuximab-based regimens demonstrated a more marked correlation compared with that between the PFS following retreatment and the interval time between the two regimens (r=0.45, P=0.11 vs. r=0.08, P=0.79). Cetuximab retreatment may provide clinical benefit to patients with mCRC who were good responders with longer periods of initial cetuximab-based therapy.

The role of T790M mutation in EGFR-TKI re-challenge for patients with EGFR-mutant advanced lung adenocarcinoma

Epidermal growth factor receptor (EGFR) T790M mutation has shown to be associated with the clinical outcomes of patients after initial EGFR-tyrosine kinase inhibitor (EGFR-TKI) therapy in EGFR-mutant advanced non-small cell lung cancer (NSCLC). However, its predictive role in EGFR-TKI re-challenge remains unknown. The present study was aimed to explore the correlation between T790M mutation and any benefits from EGFR-TKI re-challenge. We retrospectively reviewed 922 consecutive patients with EGFR-mutant non-small cell lung cancer (NSCLC) patients administered with gefitinib/erlotinib at Guangdong General Hospital. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR) and disease control rate (DCR) were analyzed respectively. In total, 66 EGFR-mutant patients with stage IV adenocarcinoma were eligible, of whom 51 underwent re-biopsy upon initial progression. Among them, 18 (35.3%) harbored T790M mutation. No statistical significant differences were seen between T790M-positive and T790M-negative patients in PFS, OS, ORR or DCR. The median PFS, median OS, ORR, and DCR of the overall 66 patients were 2.0 months, 6.8 months, 6.1% and 39.4%, respectively. Good performance status (PS) was found to be independent favorable prognostic factor and long TKI-free interval to be associated with superior PFS. In conclusion, T790M mutation might not predict the clinical outcomes in first-generation EGFR-TKI re-challenge. Based on the poor efficacy from our data, re-challenge of first-generation EGFR-TKIs could not be recommended routinely, but for those with good PS and long TKI-free interval, it might be an alternative option.

Successful clozapine re-challenge following myocarditis

OBJECTIVE

To explore the evidence around clozapine re-challenge following myocarditis.

CONCLUSION

This case adds to the 17 cases of clozapine re-challenge following myocarditis, of which 71% were successful (12 cases). This demonstrates that re-challenge could be performed safely and effectively in the context of clozapine-induced myocarditis, if accompanied by a strict and rigorous monitoring protocol.

Efficacy of Ethinylestradiol Re-challenge for Metastatic Castration-resistant Prostate Cancer

BACKGROUND

There has recently been renewed interest in the use of estrogens as a treatment strategy for castration-resistant prostate cancer (CRPC). The purpose of this study was to evaluate the feasibility and efficacy of ethinylestradiol re-challenge (re-EE) in the management of CRPC.

PATIENTS AND METHODS

Patients with metastatic CRPC who received re-EE after disease progression on prior EE and other therapy were retrospectively reviewed for prostate-specific antigen (PSA) response, PSA progression-free survival (P-PFS) and adverse events.

RESULTS

Thirty-six re-EE treatments were performed for 20 patients. PSA response to the initial EE treatment was observed in 14 (70%) patients. PSA response to re-EE was 33.3% in 36 re-EE treatments. The median P-PFS for patients treated with initial and re-EE was 7 months and 4 months, respectively. Interestingly, PSA response to re-EE was observed even in non-responders to initial EE, and those treated with multiple re-EE. No patients developed cardiovascular or thromboembolic events.

CONCLUSION

Re-EE may be safely repeated several times and can lead to a prolonged disease control in selected patients. Re-challenge with EE appears to be a reasonable option worth considering for patients with metastatic CRPC.

Statin tolerability: In defence of placebo-controlled trials

BACKGROUND

Statin intolerance is a barrier to effective lipid-lowering treatment. A significant number of patients stop prescribed statins, or can take only a reduced dose, because of adverse events attributed to the statin, and are then considered statin-intolerant.

METHODS

Examination of differences between statin and placebo in withdrawal rates due to adverse events - a good measure of tolerability - in statin cardiovascular outcome trials in patients with advanced disease and complex medical histories, who may be more vulnerable to adverse effects. The arguments commonly used to dismiss safety and tolerability data in statin clinical trials are examined.

RESULTS

Rates of withdrawal due to adverse events in trials in patients with advanced disease and complex medical histories are consistently similar in the statin and placebo groups. We find no support for arguments that statin cardiovascular outcome trials do not translate to clinical practice.

CONCLUSIONS

Given the absence of any signal of intolerance in clinical trials, it appears that statin intolerance in the clinic is commonly due to the nocebo effect causing patients to attribute background symptoms to the statin. Consistent with this, over 90% of patients who have stopped treatment because of an adverse event can tolerate a statin if re-challenged. Consequently, new agents, including monoclonal antibodies to proprotein convertase subtilisin/kexin type 9, will be useful when added to statin therapy but should rarely be used as a statin substitute.

Retreatment of men with metastatic castrate-resistant prostate cancer with abiraterone

BACKGROUND

Abiraterone acetate (AA), oral CYP17 inhibitor, is an active agent in the treatment of metastatic castrate-resistant prostate cancer (mCRPC).

METHODS

We (R.L.A and N.A) retrospectively evaluated outcome in 12 men who were re-treated with AA following prior treatment with AA at the Princess Margaret Cancer Centre.

RESULTS

All men were heavily pre-treated for mCRPC with a median of four prior lines of therapy, one of which was AA (given either pre- or post-chemotherapy). Eleven out of 12 (92%) men stopped their first treatment course of AA due to progression and one stopped for financial reasons. Seven men had a PSA decrease ≥50% following their first AA treatment, of which three (46%) had a PSA decrease ≥50% to AA re-treatment. The responses to AA re-treatment were generally short-lived with a median biochemical progression-free survival of 2.3 months and median treatment duration of 3.2 months. No PSA responses to AA re-treatment were seen in five men who did not have an initial PSA response to AA.

CONCLUSIONS

Our data suggest that AA re-challenge may have limited benefit in select men with mCRPC, and warrants further formal research.