Faculty Bibliography

Biological drugs are vital but often high-cost components of cancer treatment. Several biosimilar versions of these drugs have been approved in Europe and/or the USA, with many more in development. However, there is some disconnect between the biosimilars that are approved for use and those accessible in clinical practice, with availability impacted by factors including patent litigation and complex healthcare insurance policies, particularly in the USA. Provided the barriers to widespread uptake can be overcome, biosimilars offer potential benefits including cost savings and improved patient access versus the reference product (RP). This article provides an up-to-date and focused perspective on the development and use of biosimilars in the haemato-oncology setting. European and US regulatory pathways governing biosimilar licensing demand that there are no clinically meaningful differences between a biosimilar and its RP. Pathways are rigorously enforced and involve comprehensive non-clinical evaluations and clinical trials in selected indications to establish the equivalence or non-inferiority of efficacy, and the comparability of safety, of the biosimilar versus its RP. 'Indication extrapolation' is only permitted if scientifically justifiable considering mechanism(s) of action, pharmacokinetics, immunogenicity and safety in relevant patient populations. Switching treatment from RP to biosimilar is supported by most available data, predominantly from indications other than cancer, and post-marketing pharmacovigilance programmes are warranted. Notably, the potential benefits of biosimilar cancer treatment may extend beyond direct cost savings: for example, the availability of biosimilars of common regimen components may help incentivise the evaluation and/or clinical use of new treatment approaches and novel drugs.

Background: The phase III MONALEESA-3 trial (NCT02422615; N=726) investigated RIB, a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, +FUL as first-line (1L) or second-line (2L) treatment for postmenopausal pts with HR+/HER2- ABC. Here we report OS and 1L progression-free survival (PFS) results.
Method(s): Postmenopausal pts with HR+/HER2-ABC were randomized 2:1 to receive RIB+ FUL or PBO + FUL in 1L and 2L settings. This is the 2nd of 3 protocol-specified OS analyses.
Result(s): At the data cutoff (3 Jun 2019), 153 pts were still on treatment (RIB, n=121 [25.0%]; PBO, n=32 [13.2%]); OS was evaluated after 275 deaths (RIB, 167 [34.5%]; PBO, 108 [44.6%]). Median follow-up was 39.4 mo. RIB + FUL demonstrated a statistically significant OS prolongation over PBO + FUL (median, NR vs 40.0 mo; HR, 0.724, 95% CI, 0.568-0.924, P=0.00455). The result crossed the prespecified Lan DeMets (O'Brien Fleming) stopping boundary (P=0.01129) for superior efficacy. Per protocol, these OS results will be considered final. OS benefit with RIB vs PBO was consistent across all subgroups, including the 1L subgroup (median, NR vs 45.1 mo; HR, 0.700 [95% CI, 0.479-1.021]) and the early-relapse/2L subgroup (median, 40.2 vs 32.5 mo; HR, 0.730 [95% CI, 0.530-1.004]). In pts receiving 1L treatment, the median PFS (descriptive analysis) with RIB + FUL vs PBO + FUL was 33.6 vs 19.2 mo (HR, 0.546 [95% CI, 0.415-0.718]). Time to progression on next-line therapy or death (PFS2) was also longer with RIB vs PBO (median, 39.8 vs 29.4 mo; HR, 0.670 [95% CI, 0.542-0.830]). The safety profile was consistent with previously published analyses.
Conclusion(s): There was a statistically significant OS prolongation with RIB over PBO, which was consistent across all subgroups. The median PFS with RIB in the 1L setting is the longest reported in a phase III trial in HR+/HER2-ABC. These data, combined with results from MONALEESA-7, confirm RIB benefit with multiple combination partners in pre- and postmenopausal pts, and support RIB as a recommended CDK4/6 inhibitor as 1L and 2L treatment in pts with HR+/HER2- ABC

Background: CT-P6 was approved by both US FDA and European Commission as a biosimilar to reference trastuzumab (RTZ). Here we report updated long term efficacy and safety.
Method(s): 549 patients with HER2 positive EBC were randomized 1:1 to CT-P6 (n=271) or RTZ (n=278) with docetaxel (Cycles 1-4) and 5-fluorouracil, epirubicin and cyclophosphamide (Cycles 5-8). After surgery, patients received CT-P6 or RTZ monotherapy to complete a total of 1 year and were followed up to 3 years from enrollment of the last patient. Stratified Cox regression and Kaplan-Meier methods were used for time to event (TTE) analyses.
Result(s): 528 patients (259 in CT-P6 and 269 in RTZ) were followed up. The median duration of follow-up was 39 months. Overall, the rates of disease-free survival (DFS) and overall survival (OS) were similar between CT-P6 and RTZ in both PPS and ITT set. The number of DFS events (42 [16.3%] in CT-P6 and 36 [13.8%] in RTZ) and OS events (18 [6.6%] in CT-P6 and 18 [6.5%] in RTZ) were comparable in ITT set. Median DFS and OS have not been reached due to an insufficient number of events. The mean LVEF was more than 60% in both groups, and no new cases of heart failure were reported during the follow-up period. Table. Summary of Long Term Efficacy Endpoints.
Conclusion(s): DFS and OS rates and cardiotoxicity at a median follow-up of 39 months support the similarity of CT-P6 and reference trastuzumab in early-stage breast cancer. (Table Presented)

Background: T-DM1 is indicated for the treatment of HER2+ metastatic BC previously treated with trastuzumab and a taxane, separately or in combination. Atezo is an anti-PD-L1 antibody that inhibits PD-L1 binding to PD-1 and B7.1 thereby restoring antitumor immunity. In a phase 3 study, the addition of atezo to nab-paclitaxel significantly improved PFS in PD-L1+ pts with metastatic triple negative BC. In KATE2 (NCT02924883), adding atezo to T-DM1 in pts with HER2+ BC did not significantly increase PFS compared to T-DM1+pbo in the ITT population, but PFS was numerically longer in PD-L1+ pts. Here, we present OS and updated safety data from KATE2.
Method(s): Pts with advanced HER2-positive BC that had progressed after treatment with trastuzumab and a taxane were randomized 2:1 to atezo 1200 mg or pbo, +TDM1 3.6 mg/kg IV q3w. Pts were grouped by tumor infiltrating PD-L1+ immune cell (IC) status: IC0 vs IC1/2/3 (<1% vs>=1%, respectively) using VENTANA SP142. The preplanned OS analysis in the ITT population was a secondary endpoint with 30% power to detect an effect. OS in PD-L1 subgroups was analyzed post-hoc.
Result(s): As of the cutoff date (11 Dec 2018), median follow-up was 19.5 mo in the atezo+T-DM1 arm and 18.2 mo in the pbo+T-DM1 arm. With 52 OS events reported, median OS was not reached in either arm. In the ITT population, 1-year OS was similar in both arms. In the PD-L1+subgroup, 1-year OS was greater in the atezo+T-DM1 arm. The safety profile was consistent with the known safety profile of each drug. Grade >=3 AEs (52.6% vs 44.8%) and serious AEs (36.1% vs 20.9%)-primarily pyrexia- were more frequent in the atezo+T-DM1 arm than in the T-DM1+pbo arm.
Conclusion(s): These data suggest a possible OS benefit with atezo+T-DM1 in PD-L1+ pts. However, given the small number of OS events, the short follow-up and lack of statistical power, further study is necessary. (Table Presented)

Introduction: CT-P6 (trastuzumab-pkrb, Herzuma) is a trastuzumab biosimilar approved for use in HER2 positive breast cancer and HER2 positive gastric cancer. CT-P6 has been shown to exhibit similar safety and efficacy profiles to its reference product, trastuzumab. Preclinical and clinical studies have been performed to prove equivalence between CT-P6 and the trastuzumab originator. Areas Covered: In this review, we examine the evidence comparing CT-P6 with its reference product, trastuzumab. Both monoclonal antibodies function to target cells that overexpress HER2 on the cell surface. Preclinical pharmacologic modeling of CT-P6 shows a similar mechanism of action to trastuzumab, similar pharmacologic properties and a phase I trial in healthy volunteers showed similar pharmacokinetics. A multicenter phase III randomized clinical trial in patients with early breast cancer showed equivalent safety and efficacy between CT-P6 and trastuzumab. One-year follow-up of patients showed identical rates of cardiotoxicity. Expert Opinion: Preclinical and clinical studies showed CT-P6 pharmacologic profile, safety and efficacy are equivalent to trastuzumab. As such, it is a safe and effective alternative for use in patients with HER2 positive breast cancer and gastric cancer. Its implementation into clinical practice can potentially increase patient access and help financially alleviate overburdened health-care systems.

PURPOSE/OBJECTIVE:The metabolic etiology of breast cancer has been explored in the past several years using metabolomics. However, most of these studies only included non-Hispanic White individuals. METHODS:To fill this gap, we performed a two-step (discovery and validation) metabolomics profiling in plasma samples from 358 breast cancer patients and 138 healthy controls. All study subjects were either Hispanics or non-Hispanic African Americans. RESULTS:A panel of 14 identified metabolites significantly differed between breast cancer cases and healthy controls in both the discovery and validation sets. Most of these identified metabolites were lipids. In the pathway analysis, citrate cycle (TCA cycle), arginine and proline metabolism, and linoleic acid metabolism pathways were observed, and they significantly differed between breast cancer cases and healthy controls in both sets. From those 14 metabolites, we selected 9 non-correlated metabolites to generate a metabolic risk score. Increased metabolites risk score was associated with a 1.87- and 1.63-fold increased risk of breast cancer in the discovery and validation sets, respectively (Odds ratio (OR) 1.87, 95% Confidence interval (CI) 1.50, 2.32; OR 1.63, 95% CI 1.36, 1.95). CONCLUSIONS:In summary, our study identified metabolic profiles and pathways that significantly differed between breast cancer cases and healthy controls in Hispanic or non-Hispanic African American women. The results from our study might provide new insights on the metabolic etiology of breast cancer.

In the original publication of the article, the sixth author name Krita A. Zanetti was mistakenly included as co-author. The corrected author group is given in the correction article. The original article has been corrected.

BACKGROUND:advanced breast cancer (ABC). Herein we present results from the subset of US patients enrolled in MONALEESA-2. PATIENTS AND METHODS/METHODS:ABC without previous treatment for advanced disease were randomized (1:1) to ribociclib 600 mg/d (3 weeks on/1 week off) with letrozole 2.5 mg/d (continuous) or placebo with letrozole. The primary end point was locally assessed PFS. RESULTS:Overall, 213 US patients were enrolled in MONALEESA-2 (ribociclib, n = 100; placebo, n = 113). Baseline characteristics were similar between treatment groups and consistent with the global population. With a median follow-up of 27 months, 38 (38%) and 29 (26%) patients in the ribociclib and placebo groups, respectively, had continued to receive treatment. Median PFS was 27.6 months with ribociclib and 15.0 months with placebo (hazard ratio, 0.53). The most common all-cause adverse events were neutropenia (ribociclib, 72.0% [n = 72]; placebo, 4.6% [n = 5]), nausea (ribociclib, 69.0% [n = 69]; placebo, 44.0% [n = 48]), and fatigue (ribociclib, 60.0% [n = 60]; placebo, 50.5% [n = 55]). Two patients (ribociclib, 2.0%; placebo, 0%) experienced febrile neutropenia. CONCLUSION/CONCLUSIONS:ABC.

Background Increased adiposity is thought to result in worse clinical outcomes in patients with breast cancer through increased estrogen production, hyperinsulinemia, insulin resistance, and activation of the phosphatidylinositol-3-kinase/AKT/mammalian target of rapamycin (mTOR) pathway. Thus, we hypothesized that the addition of metformin to everolimus and exemestane, could lead to better outcomes in overweight and obese patients with metastatic, hormone receptor-positive, HER2-negative breast cancer. We conducted a phase II trial to evaluate the efficacy and safety of the combination of metformin, everolimus and exemestane in overweight and obese postmenopausal women with metastatic, hormone receptor-positive, HER2-negative breast cancer. Methods Twenty-two patients with a body mass index ≥25 kg/m² were treated with metformin 1000 mg twice daily, everolimus 10 mg daily and exemestane 25 mg daily. Median progression-free (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Results Median PFS and OS were 6.3 months (95% confidence interval [CI]: 3.8-11.3 months) and 28.8 months (95% CI: 17.5-59.7 months), respectively. Five patients had a partial response and 7 had stable disease for ≥24 weeks yielding a clinical benefit rate of 54.5%. Compared with overweight patients, obese patients had an improved PFS on univariable (p = 0.015) but not multivariable analysis (p = 0.215). Thirty-two percent of patients experienced a grade 3 treatment-related adverse event (TRAE). There were no grade 4 TRAEs and 7 patients experienced a grade 3 TRAE. Conclusion The combination of metformin, everolimus and exemestane was safe and had moderate clinical benefit in overweight and obese with patients metastatic, hormone receptor-positive, HER2-negative breast cancer.

Immunotherapy is emerging as a new treatment modality in breast cancer. After long-standing use of endocrine therapy and targeted biological therapy, improved understanding of immune evasion by cancer cells and the discovery of selective immune checkpoint inhibitors have created novel opportunities for treatment. Single-drug therapies with monoclonal antibodies against programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have shown little efficacy in patients with metastatic breast cancer, in part because of the low number of tumour-infiltrating lymphocytes in most breast cancers. There is growing interest in the development of combinations of immunotherapy and molecularly targeted therapies for metastatic breast cancer. In this Personal View, we review the available data and ongoing efforts to establish the safety and efficacy of immunotherapeutic approaches in combination with HER2-targeted therapy, inhibitors of cyclin-dependent kinases 4 and 6, angiogenesis inhibitors, poly(ADP-ribose) polymerase inhibitors, as well as chemotherapy and radiotherapy.