Significant Improvement In Objective Response Rate Research Articles

Comparison of zuberitamab plus CHOP versus rituximab plus CHOP for the treatment of drug-naïve patients diagnosed with CD20-positive diffuse large B-cell lymphoma: a phase 3 trial

BackgroundIn patients with untreated CD20-positive diffuse large B-cell lymphoma (DLBCL), a phase 3 trial was carried out to evaluate the efficacy and safety of zuberitamab plus CHOP (cyclophosphamide, doxorubicin, vincristine,...

Incorporation of PD-1 blockade into induction chemotherapy improved tumor response in patients with locoregionally advanced nasopharyngeal carcinoma in a retrospective patient cohort

ObjectiveTo investigate the short-term efficacy and safety of induction chemotherapy (IC) combined with anti-PD-1 immunotherapy in locoregionally advanced nasopharyngeal carcinoma (LA-NPC). MethodsA total of 217 patients diagnosed with LA-NPC at the First Affiliated Hospital of Nanchang University, including 67 who received IC combined with anti-PD-1 and 150 who received IC, were retrospectively enrolled. Efficacy was evaluated at the end of the IC cycles and one month after radiotherapy based on RECIST v1.1 criteria. Acute toxicities were graded based on the CTCAE v5.0 criteria. Quantitative variables were compared by unpaired t-tests, and categorical variables were evaluated by Fisher Freeman-Halton test or Pearson Chi-square test. ResultsAt the end of all induction therapy cycles, the objective response rate (ORR) of the IC + anti-PD-1 group was 88.1 % (59/67) as opposed to 70.0 % (105/150) in the IC group. Subgroup analysis showed that patients in both stage Ⅲ and ⅣA achieved a significant improvement in ORR with the inclusion of anti-PD-1 therapy. Patients with T3-4 or N2-3 category appeared to benefit more from anti-PD-1 compared to patients with T1-2 or N0-1 category. However, neither ORR nor the complete response (CR) rate was significantly different between the two treatment groups one month after the end of radiotherapy. In addition, the frequency of Grade 3–4 adverse events were also similar in both groups. ConclusionsIC combined with anti-PD-1 immunotherapy significantly improved the ORR of LA-NPC patients after induction therapy compared to IC alone.

Neoadjuvant chemotherapy combined with endocrine therapy for hormone receptor-positive breast cancer: A systematic review and meta-analysis.

This study aimed to conduct a comparative analysis of the efficacy and safety of neoadjuvant chemotherapy combined with endocrine therapy against the backdrop of single neoadjuvant chemotherapy or endocrine therapy, specifically in the context of hormone receptor-positive (HR+) breast cancer treatment. We conducted a thorough literature search across several databases, including China National Knowledge Infrastructure, Wanfang, Weipu, Chinese Journal Full-text Database, PubMed, Web of Science, Cochrane Library, and EMBASE, adhering to the guidelines outlined in the PRISMA statement. Our specific focus was on identifying randomized controlled trials that directly compared the combined approach of neoadjuvant chemotherapy and endocrine therapy with single chemotherapy or endocrine therapy in the context of treating HR+ breast cancer. Subsequently, we utilized statistical packages implemented in R software to perform comparative analyses of key clinical indicators, encompassing the complete response, objective response rate (ORR), disease control rate, pathological complete response (pCR), and adverse reactions. A total of 11 randomized controlled trials, involving 1359 patients, all of whom met our inclusion criteria and were thus included in our comprehensive analysis. Within this cohort, 688 patients (50.63%) administered neoadjuvant chemotherapy combined with endocrine therapy (NCET), 642 patients (47.24%) received neoadjuvant chemotherapy (NCT) alone, while 29 patients (2.13%) underwent neoadjuvant endocrine therapy (NET) alone. The results of our meta-analysis revealed that NCET exhibited a statistically significant enhancement in both ORR and pCR (P < .05). Nonetheless, when compared to NCT or NET, NCET did not yield a significant impact on complete response, disease control rate, and safety (P > .05). In addition, NCET demonstrated a significant improvement in ORR among patients with HR+, HER2-negative breast cancer (P < .05). However, it was also linked to a heightened incidence of serious adverse reactions within this particular patient subgroup (P < .05). The combination of Neoadjuvant chemotherapy and endocrine therapy stands out as a significant contributor to enhancing the ORR and pCR for HR+ breast cancer patients. For breast cancer patients with HER2- status, NCET demonstrates a remarkable improvement in ORR but is also associated with the emergence of adverse reactions.

ORIENT-32: Updated characterization of response to sintilimab plus bevacizumab biosimilar (IBI305) vs sorafenib for unresectable hepatocellular carcinoma.

570 Background: ORIENT-32 trial (NCT03794440) assessed sintilimab (anti-PD-1 antibody) plus a bevacizumab biosimilar (anti-VEGF antibody) versus sorafenib (Sor) as first-line treatment for unresectable HCC and demonstrated a significant improvement in both overall survival and progression-free survival. Here we report the updated results of objective response rate (ORR), time to response (TTR), duration of response (DoR) and depth of response (DpR). Methods: 571 eligible patients (pts) with unresectable HCC were enrolled and randomized (2:1) to receive sintilimab (200 mg IV Q3W) plus IBI305 (15 mg/kg IV Q3W) or Sor (400 mg orally, BID) until disease progression or unacceptable toxicity. Tumors were evaluated using Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1)and HCC-modified RECIST (mRECIST). ORR, TTR, DoR, and DpR were analyzed. The DpR was defined as the minimum percentage of (1) sum of longest diameter (SLD) change and (2) longest diameter (LD) change described as mean (standard deviation, SD). Results: At the data cutoff on Dec 30th, 2021, the median follow-up time was 26.7 months. The ORR in sintilimab plus IBI305 and Sor group was 21.0% (77/367) vs 4.7 (8/169) per RECIST 1.1 and 25.1% (92/367) vs 7.7% (13/169) per mRECIST. The median TTR in sintilimab plus IBI305 group was 2.8 (2.4–3.3) months per RECIST 1.1 and 2.6 (1.6–2.9) months per mRECIST. The median DoR in sintilimab plus IBI305gourp was 20.3 (12.3-NE) months per RECIST 1.1. The minimum percentage of SLD change was larger in the sintilimab plus IBI305 arm than in the Sor arm: (−13.4% (35.8) vs 3.2%(26.5) per RECIST 1.1). Similarly, the LD change in the largest liver lesion also favored sintilimab plus IBI305 arm (−27.6% (31.6) vs −11.5% (20.9)), including larger tumors (≥7 cm; −21.2% (30.4) vs −9.9% (23.7)) all per RECIST 1.1. Conclusions: Sintilimab plus IBI305 showed a significant improvement in ORR, TTR, DOR and DpR vs Sor in unresectable HCC. Clinical trial information: NCT03794440 .

Combining of chemotherapy with targeted therapy for advanced biliary tract cancer: A systematic review and meta-analysis.

BACKGROUNDTargeted therapy (TT) has resulted in controversial efficacy as first-line treatment for biliary tract cancer (BTC). More efficacy comparisons are required to clarify the overall effects of chemotherapy (CT) combined with TT and CT alone on advanced BTC.AIMTo conduct a meta-analysis of the available evidence on the efficacy of CT combined with TT for advanced BTC.METHODSThe PubMed, EMBASE, ClinicalTrials, Scopus and Cochrane Library databases were systematically searched for relevant studies published from inception to August 2022. Only randomized clinical trials (RCTs) including comparisons between the combination of gemcitabine-based CT with TT and CT alone as first-line treatment for advanced BTC were eligible (PROSPERO-CRD42022313001). The odds ratios (ORs) for the objective response rate (ORR) and hazard ratios (HRs) for both progression-free survival (PFS) and overall survival (OS) were calculated and analyzed. Subgroup analyses based on different targeted agents, CT regimens and tumor locations were prespecified.RESULTSNine RCTs with a total of 1361 individuals were included and analyzed. The overall analysis showed a significant improvement in ORR in patients treated with CT + TT compared to those treated with CT alone (OR = 1.43, 95%CI: 1.11-1.86, P = 0.007) but no difference in PFS or OS. Similar trends were observed in the subgroup treated with agents targeting epidermal growth factor receptor (OR = 1.67, 95%CI: 1.17-2.37, P = 0.004) but not in the subgroups treated with agents targeting vascular endothelial growth factor receptor or mesenchymal-epithelial transition factor. Notably, patients who received a CT regimen of gemcitabine + oxaliplatin in the CT + TT arm had both a higher ORR (OR = 1.75, 95%CI: 1.20-2.56, P = 0.004) and longer PFS (HR = 0.83, 95%CI: 0.70-0.99, P = 0.03) than those in the CT-only arm. Moreover, patients with cholangiocarcinoma treated with CT + TT had significantly increased ORR and PFS (ORR, OR = 2.06, 95%CI: 1.27-3.35, PFS, HR = 0.79, 95%CI: 0.66-0.94).CONCLUSIONCT + TT is a potential first-line treatment for advanced BTC that leads to improved tumor control and survival outcomes, and highlighting the importance of CT regimens and tumor types in the application of TT.

Trastuzumab deruxtecan (T-DXd; DS-8201) in patients (pts) with HER2-expressing unresectable or recurrent biliary tract cancer (BTC): An investigator-initiated multicenter phase 2 study (HERB trial).

4006 Background: BTCs have an aggressive tumor biology with limited treatment options. With a HER2-positivity rate of 5–20% in BTCs, case series and small clinical trials have shown signs of activity for HER2 blockade in these pts. T-DXd is an antibody-drug conjugate composed of a humanized monoclonal anti-HER2 antibody, a cleavable linker, and a topoisomerase I inhibitor. The HERB trial is an investigator-initiated, multicenter, single-arm phase 2 trial of T-DXd in pts with HER2-expressing BTCs. Methods: Centrally confirmed HER2-expressing (HER2-positive: IHC3+ or IHC2+/ISH+, and HER2-low-expressing [HER2-low]: IHC/ISH status of 0/+, 1+/-, 1+/+, or 2+/-) pts with BTCs who were refractory or intolerant to gemcitabine containing regimen received 5.4 mg/kg of T-DXd every 3 weeks. The primary endpoint was the confirmed objective response rate (ORR) in HER2-positive pts by independent central review. The sample size of 22 had 80% power with one-sided alpha error of 5%; threshold ORR, 15%; and expected ORR, 40%. The ORR, disease control rate (DCR), progression-free survival (PFS), overall survival (OS) in HER2-positive/-low pts, and incidence of treatment-emergent adverse events (TEAEs) were assessed as secondary endpoints. Results: A total of 32 pts, 24 with HER2-positive and 8 with HER2-low BTCs, received T-DXd. Twenty-two pts with HER2-positive, excluding 2 ineligible pts, were identified for primary efficacy analysis. Among the 22 pts, IHC3+ and IHC2+/ISH+ were 45.5% and 54.5%, primary sites: gallbladder/extrahepatic/intrahepatic/Vater were 11/6/3/2, median number of prior regimens was 2 (range, 1–4). The confirmed ORR in HER2-positive pts was 36.4% (8/22; 2 CR and 6 PR; 90% CI, 19.6–56.1), indicating statistically significant improvement in ORR (P = 0.01). The DCR, median (m) PFS, mOS were 81.8% (95% CI, 59.7–94.8), 4.4 months (mo) (95% CI, 2.8–8.3), 7.1 mo (95% CI, 4.7–14.6), respectively. In addition, encouraging efficacy were seen even in HER2-low pts; ORR, DCR, mPFS, and mOS were 12.5% (1/8; 1 PR; 95% CI, 0.3–52.7), 75.0% (95% CI, 34.9–96.8), 4.2 mo (95% CI, 1.3–6.2), and 8.9 mo (95% CI, 3.0–12.8), respectively. In the safety analysis set (n = 32), TEAEs of &gt; = grade (G) 3 occurred in 81.3% (26/32); the common TEAEs were anemia (53.1%), neutropenia (31.3%), and leukopenia (31.3%). TEAEs leading to drug discontinuation occurred in 8 pts (25.0%). Eight pts (25.0%) had interstitial lung disease (ILD; G1/G2/G3/G5 were 3/1/2/2) not adjudicated by an independent committee. Conclusions: T-DXd showed promising activity in pts with HER2-expressing BTCs. Although the safety profile was generally consistent with other T-DXd studies, ILD, an important identified risk of T-DXd, requires more careful monitoring and intervention. These results support further exploration of T-DXd in this patient population. Clinical trial information: JMA-IIA00423.

Associations with response to Poly(ADP-ribose) Polymerase (PARP) inhibitors in patients with metastatic breast cancer

PARP inhibitors (PARPi) have modest antitumor activity in patients with advanced breast cancer and mutation in BRCA. It is unclear whether some subgroups derive greater benefit from treatment. MEDLINE and EMBASE were searched from inception to March 2021 to identify trials of PARPi in patients with metastatic breast cancer. Objective response rate (ORR) and clinical benefit rate (CBR) to PARPi were extracted and pooled in a meta-analysis using the Mantel Haenszel random effects model. Meta-regression explored the influence of patient and tumor characteristics on ORR and CBR. For randomized trials, hazard ratio comparing PARPi to control therapy were pooled using inverse variance and random effects. Analysis included 43 studies comprising 2409 patients. Among these, 1798 (75%) patients had BRCA mutations and 1146 (48%) were triple negative. In 10 studies (28%; n = 680 patients), the PARPi was given in combination with platinum-based chemotherapy. Weighted mean ORR was 45%; 64% when combined with platinum vs 37% with PARPi monotherapy (p < 0.001). Previous platinum-based chemotherapy was associated with lower ORR (p = 0.02). Compared to standard chemotherapy, progression-free survival was improved (HR 0.64, p < 0.001), but there was no difference in overall survival (HR 0.87, p = 0.06). There were no differences in ORR or CBR between BRCA1 and BRCA2 mutations. PARPi are more active in combination with platinum than as monotherapy, with lower response if given as monotherapy after platinum exposure. Significant improvements in ORR translated to modest improvement in progression-free, but not overall survival. There was no association between ORR and BRCA mutations.

Expanding the immunotherapy roadmap for hepatocellular carcinoma.

In a recent Lancet Oncology article, Yau etal. report the CheckMate 459 trial results. This is the first phase III trial comparing the single-agent anti-programmed death protein 1 (PD-1) therapy nivolumab to the tyrosine kinase inhibitor sorafenib for treatment-naive patients with advanced hepatocellular carcinoma.

Efficacy and safety of first-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) combined with chemotherapy or antiangiogenic therapy as first-line treatment in patients with EGFR-mutant non-small cell lung cancer: A systematic review and meta-analysis.

We conducted a meta-analysis to synthesize the results of published randomized controlled trials conducted to evaluate the efficacy and safety of epidermal growth factor receptor - tyrosine kinase inhibitors (EGFR-TKIs) combined with chemotherapy or antiangiogenic therapy. PubMed, EMBASE, Cochrane Library and ClinicalTrials.gov databases were searched and literatures from international conferences were read to identify eligible studies. The primary endpoints were objective response rate (ORR) and progression free survival (PFS). The secondary endpoints were disease control rate (DCR), overall survival (OS) and treatment-emergent adverse events (TEAEs). 10 studies, all on first-generation EGFR-TKI combination therapy, involving 2367 patients were included. Combination therapy resulted in significant improvements in ORR (RR: 1.11, 95% CI: 1.06-1.17, P < 0.001), DCR (RR: 1.03, 95% CI: 1.01-1.05, P = 0.007), PFS (HR: 0.56, 95% CI: 0.51-0.62, P < 0.001), OS (HR: 0.74, 95% CI: 0.64-0.84, P = 0.002) over monotherapy. This improvement was more apparent in the EGFR-TKIs combination chemotherapy group, and indirect comparisons revealed that EGFR-TKIs combined with chemotherapy appeared to be superior to combined with antiangiogenic therapy in ORR (RR: 1.19, 95% CI: 1.07-1.32), DCR (RR: 1.04, 95% CI: 1.02-1.08), and OS (HR: 0.79, 95% CI: 0.66-0.96). Of additional concern is the increased incidence of TEAEs in combination therapy. As a first-line treatment for patients with EGFR-mutated advanced non-small cell lung cancer (NSCLC), first-generation EGFR-TKIs combined with chemotherapy or antiangiogenic therapy was associated with significant improvement in ORR, DCR, PFS and OS compared with monotherapy.

Efficacy and safety of systemic treatments for patients with recurrent/metastatic head and neck squamous cell carcinoma: A systematic review and network meta-analysis.

e18001 Background: A variety of systemic chemotherapy regimens have been used for recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). However, most guidelines were derived from a single clinical trial, and no studies have comprehensively compared their efficacy and safety. This study is aimed to compare the efficacy and safety of systemic chemotherapies for patients with R/M HNSCC. Methods: We conducted a systematic review of published studies in PubMed, Embase, Web of Science, and Cochrane Library databases up to July 31, 2020. Studies were included if they were randomized controlled clinical trials including treatment regimens recommended by the latest NCCN guidelines. Eligible studies should report at least one of the following outcomes: overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and ≥3 adverse events rate (AEs). Literature screening, data extraction and quality assessment were independently conducted by two researchers. Disputes were settled by a panel of other researchers. Network meta-analysis was used to compare the efficacy and safety of various treatment regimens. Heterogeneity and consistency using the Bayesian model were evaluated in the network meta-analysis. Results: Eighteen eligible trials involving 4930 patients and 15 treatment regimens were included. Cetuximab/platinum/5-FU regimen showed higher ORR values than the following agents, including cisplatin/5-FU (odds ratio 2.96, 95% credible interval 1.42 to 6.15), cisplatin (5.43, 1.90-15.54), 5-FU (8.12, 2.22-29.61), methotrexate (8.25, 2.86-23.79), cetuximab (10.16, 1.44-71.48), and afatinib (3.64, 1.00-13.32). Immunotherapy regimens pembrolizumab/platinum/5-FU and pembrolizumab alone also showed significantly higher ORR values than these agents, while nivolumab alone showed higher ORR than the single agents. However, no significant difference was observed between Cetuximab/platinum/5-FU and pembrolizumab/platinum/5-FU. Regarding ≥3 AEs, cisplatin/paclitaxel caused the highest toxicity. No significant difference was observed on OS and PFS among all these treatment regimens. Conclusions: Cetuximab/platinum/5-FU, pembrolizumab/platinum/5-FU or pembrolizumab alone displayed high ORR with low AE rate. Nivolumab also showed better efficacy than other single agents. Although it was reported that pembrolizumab/platinum/5-FU showed better efficacy than cetuximab/platinum/5-FU, we did not find a statistically significant improvement in ORR, OS or PFS when comparing the two regimens. Therefore, further prospective trials comparing these treatment regimens remain warranted.

1844O - Durable anti-tumor activity of the multi-targeted inhibitor lenvatinib in patients with advanced or metastatic thymic carcinoma: Preliminary results from a multicenter phase II (REMORA) trial

1844O - Durable anti-tumor activity of the multi-targeted inhibitor lenvatinib in patients with advanced or metastatic thymic carcinoma: Preliminary results from a multicenter phase II (REMORA) trial

Exploratory analysis of the effect of taselisib on downstream pathway modulation and correlation with tumor response in ER-positive/HER2-negative early-stage breast cancer from the LORELEI trial.

1050 Background: Taselisib (T) is an oral, potent, selective inhibitor of Class I PI3-kinase with enhanced activity against PIK3CA mutant cancer cells. Results from the LORELEI trial have demonstrated a significant improvement in ORR (objective response rate) by centrally assessed magnetic resonance imaging in all randomized patients as well as in the PIK3CA mutant (MT) cohort treated with neoadjuvant T plus letrozole (L) compared to placebo (P) plus L. Here we present the results of exploratory analyses of selected pathway-related phosphoproteins. Methods: Baseline (BL) and week3 (W3) tumor biopsies were obtained from 334 patients enrolled in the trial. Phosphoproteins (pAKT, pPRAS40 and pS6) were analyzed by IHC. BL levels as well as changes from BL to W3 were correlated with response assessed either by ORR or cell cycle arrest (Ki67 at W3 &lt; 2.7%). Results: In the overall population, BL phosphoproteins levels were similar between the T and P arms. Higher pAKT (p &lt; 0.001) and pPRAS40 (p = 0.004) levels were observed in MT vs wild-type (WT), whereas the opposite result was found for pS6 (p = 0.03). Treatment-induced absolute changes of phosphoproteins adjusted for BL levels were not significantly different between the T and P arms in the overall population, except for pPRAS40 with higher decrease in the T arm (p = 0.014). After stratification for PIK3CA genotype, a significantly greater decrease in expression levels was observed for pPRAS40 (p &lt; 0.001) and pS6 (p = 0.020) in MT tumors treated with T. The treatment effects were not significantly different in the WT population. A trend for an association between decrease in pS6 levels at W3 and improved ORR was observed in the MT (p = 0.08) and T (p = 0.09) subgroups. The magnitude of pS6 suppression at W3 was higher in tumors achieving a cell cycle arrest in the MT/T subgroup (biserial correlation = -0.473). Conclusions: Exploratory analyses of phosphoproteins showed bioactivity of taselisib as indicated by downstream pathway suppression. Translational research aiming to integrate these results with additional exploratory biomarkers data is currently ongoing. Clinical trial information: NCT02273973.

Effectiveness of temozolomide combined with whole brain radiotherapy for non-small cell lung cancer brain metastases.

BackgroundWe performed a retrospective analysis to compare the efficacy of whole brain radiotherapy (WBRT) combined with temozolomide (TMZ) versus WBRT alone as first‐line treatment for brain metastases (BM).MethodsSeventy‐eight non‐small cell lung cancer patients with BM were observed, including 45 patients who received WBRT plus TMZ (TMZ + WBRT) and 33 patients who received WBRT alone (WBRT). The primary outcome was overall survival (OS). Secondary outcomes included progression‐free survival (PFS), objective response rate (ORR), and adverse events.ResultsThe TMZ + WBRT arm achieved significant improvement in ORR (P = 0.0108) compared to the WBRT arm. PFS in the TMZ + WBRT arm was significantly longer than in the RT arm (6.0 vs. 3.5 months; P = 0.038). OS was not significantly different between the two arms. Although increased adverse reactions were experienced in the TMZ + WBRT arm, patients were tolerant of the side effects. Statistically significant differences in neurocognitive function and quality of life were observed between the arms at six months.ConclusionConcomitant TMZ + WBRT compared to WBRT alone significantly increases ORR and median PFS in patients with BM, but no remarkable difference in median OS was found. Adding TMZ to the treatment strategy could prevent neurocognitive function and quality of life from deteriorating. Although the addition of TMZ increases the incidence of adverse effects, no significant difference was observed. Thus, TMZ is safe and effective.

Abstract PD5-04: Ki67 changes and PEPI score in the LORELEI trial: A phase II randomized, double-blind study of neoadjuvant letrozole plus taselisib versus letrozole plus placebo in postmenopausal women with ER-positive/HER2-negative early-stage breast cancer

Abstract Background: Taselisib is an oral, potent, selective inhibitor of Class I PI3-kinase (PI3K) alpha, gamma, and delta isoforms with enhanced activity against PIK3CA mutant cancer cells. LORELEI trial demonstrated a significant improvement in ORR (objective response rate) centrally assessed by MRI with neoadjuvant taselisib plus letrozole compared to letrozole plus placebo in all randomized patients as well as in the PIK3CA mutant cohort (Saura et al, ESMO 2017). Methods: 334 postmenopausal women with newly diagnosed ER+/HER2-, untreated, Stage I-III operable breast cancer and evaluable tumor tissue for PIK3CA genotyping were randomized (1:1) to receive daily letrozole (2.5 mg) with either taselisib (4 mg on a 5 days on/ 2 days off schedule) or placebo for 16 weeks, followed by surgery. Tumor tissue collection was performed at baseline, week 3 (W3) and at surgery. Secondary objectives included, but were not restricted to, ORR assessed by MRI in patients with PIK3CA wild type (WT) tumors, ORR using alternative methods of tumor assessment (ultrasound, mammogram and clinical breast exam) in all patients and patients with PIK3CA mutant and WT tumors, central assessment of Ki67 at different timepoints (baseline, W3 and surgery), and the centrally derived PEPI score. Central Ki67 was assessed by two independent readers blinded to treatment arms and PIK3CA status (Vall D'Hebron Institute of Oncology, Barcelona). Results: ORR by centrally assessed MRI was similar in the two treatment arms in patients with PIK3CA WT tumors (45.7 vs 40.4% for taselisib and placebo, respectively). ORR assessed by breast US was also significantly higher with taselisib compared to placebo in all randomized patients and in the PIK3CA mutant cohort. The highest concordance rate between MRI and other imaging modalities was found with breast ultrasound (53.7%). Centrally assessed Ki67 changes are reported in Table 1. Ki67 values decreased from baseline to W3 and from baseline to surgery in both treatment arms. No significant differences in the decrease of Ki67 values between treatment arms were detected. Unplanned analysis of Complete Cell Cycle Arrest (CCCA) at W3 was numerically higher with taselisib than with placebo in all randomized patients (49.6% vs 38.5%) and in the PIK3CA mutant cohort (60.9% vs 47.5%). Due to the variability in timing between the last dose of taselisib (median time 11 days; interquartile range 6-16 days) and tissue collection at surgery, considering the half-life of taselisib of approximately 40 hours, centrally derived PEPI score is not interpretable. Ki67 proportional changes, %Taselisib + letrozolePlacebo + letrozoleBaseline to W3All patients-83.8-80.4PIK3CA mutant-84.5-79.1PIK3CA WT-82.8-81.1Baseline to surgeryAll patients-75.6-80.5PIK3CA mutant-71.9-79.9PIK3CA WT-78.2-81.2 Conclusion: Among the investigated alternative methods for assessing ORR, breast ultrasound performed similar to MRI. Decrease in the Ki67 values from baseline to W3 and to surgery were observed in both treatment arms. The time interval between taselisib cessation and tissue collection at surgery are being further investigated. Clinical trial information: NCT02273973 Citation Format: de Azambuja E, Saura C, Nuciforo P, Frantal S, Oliveira M, Zardavas D, Jallitsch-Halper A, de la Pena L, Dubsky P, Lombard JM, Vuylsteke P, Castaneda Altamirano C, Sanchez C, Ballestrero A, Colleoni M, Santos Borges G, Ciruelos E, Bardia A, Fornier M, Boer K, Wilson TR, Stout TJ, Hsu JY, Shi Y, Piccart M, Baselga J, Gnant M. Ki67 changes and PEPI score in the LORELEI trial: A phase II randomized, double-blind study of neoadjuvant letrozole plus taselisib versus letrozole plus placebo in postmenopausal women with ER-positive/HER2-negative early-stage breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD5-04.

Efficacy and safety of anti-epidermal growth factor receptor therapy compared with anti-vascular endothelial growth factor therapy for metastatic colorectal cancer in first-line and second-line therapies: a meta-analysis.

AimThis study aimed to compare anti-epidermal growth factor receptor (anti-EGFR) therapy and anti-vascular endothelial growth factor therapy as first-line and second-line therapies in patients with KRAS exon 2 codon 12/13 wild-type (KRAS-WT) metastatic colorectal cancer (mCRC).MethodsMajor databases were systematically searched. The hazard ratio (HR), odds ratio (OR), and 95% confidence intervals (95% CIs) were used to estimate the effect measures. Review Manager software version 5.3 was used for statistical analysis.ResultsSeven trials including ten articles were eligible in the meta-analysis. The patients treated with anti-EGFR as first-line therapy showed a longer overall survival (OS) for KRAS-WT and all RAS wild-type (RAS-WT) mCRC (HR =0.81, 95% CI: 0.72–0.92, P<0.01, n=5; HR =0.78, 95% CI: 0.66–0.93, P<0.01, n=3, respectively). The objective response rate (ORR) was better with the anti-EGFR therapy for KRAS-WT and all RAS-WT mCRC (OR =1.32, 95% CI: 1.11–1.56, P<0.01, n=5; OR =1.55, 95% CI: 1.21–2.00, P<0.01, n=3, respectively). There was no difference in progression-free survival (PFS) for KRAS-WT mCRC and all RAS-WT mCRC between the two groups (HR =1.00; 95% CI: 0.92–1.09, P=0.99, n=4; HR =0.92, 95% CI: 0.71–1.19, P=0.52, n=3, respectively). In addition, two trials provided data on the second-line therapy; there was no significant difference in OS and PFS for the second-line therapy, but a significant improvement in ORR was found in the anti-EGFR group (OR =1.91, 95% CI: 1.16–3.16, P=0.01, n=2). No difference in the conversion therapy (OR =1.34; 95% CI: 0.91–1.99; P=0.14, n=4) was observed between the two therapies.ConclusionOur results indicate that anti-EGFR therapy is superior to anti-vascular endothelial growth factor therapy for OS and ORR as a first-line therapy for KRAS-WT mCRC. In the second-line therapy, there was no significant difference in the survival outcomes on the basis of OS and PFS between the two groups. However, ORR improved significantly in the anti-EGFR group.

Abstract 2273: Targeting the PI3K/AKT/mTOR pathway for the treatment of metaplastic breast cancer: Does location of PIK3CA mutation or histology affect response

Abstract Background: Metaplastic breast cancers (MpBCs) are a chemo-refractory group of tumors that contain a component of squamous and/or mesenchymal differentiation identifiable by light microscopy. MpBCs contain a high frequency of aberrations in the PI3K/AKT/mTOR pathway, making this pathway a potential target for therapy. Methods: Patients with advanced MpBC (N = 52) were treated with liposomal doxorubicin (D), bevacizumab (A) and the mTOR inhibitors temsirolimus (T) or everolimus (E). D and A were administered IV on day 1 with T (IV on days 1, 8 and 15) or E (continuous daily oral administration) using 21 day cycles. All tumors were evaluated to assess histology of metaplasia (spindle, mixed spindle vs non-spindle cell). Response was assessed every 6 weeks using RECIST. When available, archived tissue was evaluated for aberrations in the PI3K pathway using standard assays. Results: Fifty-two MpBC patients were treated with DAT (N = 39) or DAE (N = 13). Median age was 58 (range 37-79); median number of prior regimens for metastatic disease was 1 (range 0-5). The objective response rate (ORR) was 21% [complete response (CR) = 4 (8%); partial response (PR) = 7 (13%)] and 10 (19%) pts had stable disease (SD)≥6 months for a clinical benefit rate (CBR) of 40%. Tissue was available in 43 pts and 32 (74%) had a PI3K pathway activating aberrations. PI3K pathway aberration was associated with a significant improvement in ORR (31 vs 0%; P = 0.04) but not CBR (44 vs 45%; P = 1.00) or progression-free survival (median 5 vs 3 months; P = 0.35). The most frequent PI3K pathway aberration was mutation in PIK3CA, occurring in 19 patients. Outcomes were similar if mutations of PIK3CA were located in the helical or kinase domain (ORR 25% vs 27%; P = 1.00 and CBR 38% vs 47%; P = 1.00, respectively). Spindle cell was the most frequent metaplastic histology seen, occurring in 18 tumors and mixed with other metaplastic histologies including squamous, chondroid and osseous in 14 additional tumors, while 20 tumors had non-spindle cell morphologies. The incidence of PI3K pathway aberration was similar across histologies (61% in spindle vs 67% in mixed spindle vs 60% in non-spindle cell). Tumors with mixed histology had lower ORR, CBR and PFS, but this was not statistically significant, likely due to small numbers in each cohort: ORR 22% in spindle vs 7% in mixed spindle vs 30% in non-spindle cell, P = 0.27; CBR 50% in spindle vs 21% in mixed spindle vs 40% in non-spindle cell, P = 0.25; and PFS median 4 months in spindle vs 2 months in mixed spindle vs 5 months in non-spindle cell, P = 0.68. Conclusions: Response to mTOR inhibition is enhanced in MpBCs with PI3K pathway aberrations. However, specific aberrations in PIK3CA do not lead to differential response to mTOR inhibition. PI3K pathway aberrations and response to mTOR inhibition are seen across all histologies of MpBC, and the response is not enhanced in particular histologies. Citation Format: Reva K. Basho, Michael Gilcrease, Rashmi K. Murthy, Thorunn Helgason, Daniel J. Booser, Daniel D. Karp, Funda Meric-Bernstam, Kenneth R. Hess, Shelley M. Herbrich, Vicente Valero, Constance Albarracin, Jennifer Litton, Mariana Chavez-MacGregor, Nuhad K. Ibrahim, James L. Murray, Kimberly B. Koenig, David Hong, Vivek Subbiah, Razelle Kurzrock, Filip Janku, Stacy Moulder. Targeting the PI3K/AKT/mTOR pathway for the treatment of metaplastic breast cancer: Does location of PIK3CA mutation or histology affect response. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2273.

Abstract P3-14-02: Targeting the PI3K/AKT/mTOR pathway for the treatment of mesenchymal triple-negative breast cancer (TNBC): Evidence of efficacy and proof of concept from a phase I trial with dose expansion of mTOR inhibition in combination with liposomal doxorubicin and bevacizumab

Abstract Background: Approximately 30% of TNBCs are characterized by microarray as claudin-low, mesenchymal or mesenchymal stem cell-like and, unlike basal TNBCs, these tumors frequently harbor aberrations in the PI3K/AKT/mTOR axis, raising the possibility of targeting this axis to enhance chemotherapy response. Assays to clinically identify mesenchymal TNBCs are under development, but published results confirm that up to 30% are metaplastic breast cancers (MpBCs), a chemo-refractory group of tumors that contain a mixture of epithelial and mesenchymal components, making them identifiable by microscopy. As such, MpBCs serve as surrogates of response for potential regimens to treat mesenchymal TNBC. Methods: Patients (pts) with advanced TNBC (N=64) were treated with liposomal doxorubicin (D), bevacizumab (A) and the mTOR inhibitors temsirolimus (T) or everolimus (E). D and A were administered IV on day 1 with T (IV on days 1, 8 and 15) or E (continuous daily oral administration) using 21 day cycles. Response was assessed every 6 weeks using RECIST. When available, archived tissue was evaluated for aberrations in the PI3K pathway using standard assays. Results: Fifty-two MpBC pts were treated with DAT (N=39) or DAE (N=13). Median age was 58 (range 37-79); median # of prior regimens for metastatic disease was 1 (range 0-5). The objective response rate (ORR) was 21% [complete response (CR)=4 (8%); partial response (PR)=7 (13%)] and 10 (19%) pts had stable disease (SD)≥6 months for a clinical benefit rate (CBR) of 40%. Tissue was available for testing in 43 pts and 32 (74%) had a PI3K pathway activating aberration (Table 1). Response According to PI3K Pathway AberrationPI3K Pathway AberrationN (%)CRPRSD≥6monthsCBRORRAny PI3K Pathway Aberration*32 (74)46444%31%PIK3CA Mutation19 (59)23447%26%p.H1047R12 (38)21350%25%p.E545K6 (19)02150%33%p.G1007R1 (3)010100%100%p.E545A1 (3)0000%0%p.H1047Y1 (3)0000%0%p.K111E1 (3)0000%0%p.E542K1 (3)0000%0%PIK3CA Amplification1 (3)010100%100%PTEN Mutation5 (16)0000%0%PTEN Loss5 (16)02040%40%AKT1 p.E17K Mutation2 (6)0000%0%AKT2 Amplification1 (3)100100%100%PIK3R1 Mutation2 (6)01050%50%NF2 Mutation1 (3)100100%100%No PI3K Pathway Aberration11 (26)00545%0%*Some tumors had &amp;gt;1 aberration detected PI3K pathway activation was associated with a significant improvement in ORR (31 vs 0%; P=0.043) but not CBR (44 vs 45%; P=1.000) or progression-free survival (median 5.1 vs 2.9 months; P=0.352). A pt with 5 year+ durable CR (on maintenance everolimus) had a mutation in NF2. To emphasize the importance of pt selection, it is notable that 12 pts with non-metaplastic TNBC were also treated with DAT, and only 1 pt had a response (CR/PR=1; SD≥6 months=0), for a CBR that was significantly worse than pts with MpBC (8 vs 40%; P=0.045). Conclusions: Using MpBC as a surrogate of response, DAT/DAE has significantly better activity in mesenchymal compared to non-selected TNBC. Response is enhanced in pts with PI3K pathway activation. DAT/DAE should be tested in non-metaplastic, mesenchymal TNBC once a diagnostic assay is available. Citation Format: Basho RK, Gilcrease M, Murthy RK, Helgason T, Booser DJ, Karp DD, Meric-Bernstam F, Wheler JJ, Valero V, Albarracin C, Litton J, Chavez-MacGregor M, Ibrahim NK, Murray JL, Koenig KB, Hong D, Subbiah V, Kurzrock R, Janku F, Moulder S. Targeting the PI3K/AKT/mTOR pathway for the treatment of mesenchymal triple-negative breast cancer (TNBC): Evidence of efficacy and proof of concept from a phase I trial with dose expansion of mTOR inhibition in combination with liposomal doxorubicin and bevacizumab. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-14-02.

REVEL: A randomized, double-blind, phase III study of docetaxel (DOC) and ramucirumab (RAM; IMC-1121B) versus DOC and placebo (PL) in the second-line treatment of stage IV non-small cell lung cancer (NSCLC) following disease progression after one prior platinum-based therapy.

LBA8006^ Background: RAM is a human IgG1 monoclonal antibody that targets the extracellular domain of VEGFR-2. The REVEL study evaluated the efficacy and safety of RAM+DOC vs. PL+DOC (DOC) in patients (pts) with stage IV nonsquamous (NSQ) and squamous (SQ) NSCLC after platinum-based therapy. Methods: Pts with NSQ and SQ stage IV NSCLC were randomized 1:1 (stratified by sex, region, ECOG PS, and prior maintenance therapy) to receive DOC 75 mg/m2 in combination with either RAM 10 mg/kg or PL on day 1 of a 21-day cycle until disease progression, unacceptable toxicity, or death. The primary endpoint was overall survival (OS). Secondary efficacy endpoints included progression-free survival (PFS), and objective response rate (ORR). Results: Between Dec 2010 and Feb 2013, 1,253 pts (26.2% SQ) were randomized (RAM+DOC: 628; DOC: 625). Pt characteristics were balanced between arms. ORR was 22.9% for RAM+DOC and 13.6% for DOC (P&lt;0.001). The hazard ratio (HR) for PFS was 0.762 (P&lt;0.0001); median PFS was 4.5 months (m) for RAM+DOC vs. 3.0m for DOC. REVEL met its primary endpoint; the OS HR was 0.857 (95% CI 0.751, 0.98; P=0.0235); median OS was 10.5m for RAM+DOC vs. 9.1m for DOC. OS was longer for RAM+DOC in most pt subgroups, including SQ and NSQ histology. Grade ≥3 adverse events (AEs) occurring in &gt;5% of pts on RAM+DOC were neutropenia (34.9% vs. 28.0%), febrile neutropenia (15.9% vs. 10.0%), fatigue (11.3% vs. 8.1%), leukopenia (8.5% vs. 7.6%), hypertension (5.4% vs. 1.9%), and pneumonia (5.1% vs. 5.8%). Grade 5 AEs were comparable between arms (5.4% vs. 5.8%), as was pulmonary hemorrhage (any grade; all pts: 2.1% vs. 1.6%; SQ pts: 3.8% vs. 2.4%). Conclusions: REVEL demonstrated a statistically significant improvement in ORR, PFS, and OS for RAM+DOC vs DOC in NSCLC pts with stage IV NSCLC as second-line treatment after platinum-based therapy. Benefits were similar in NSQ and SQ pts, and no unexpected AEs were identified. Clinical trial information: NCT01168973.

Bevacizumab in the treatment of ovarian cancer: a meta-analysis from four phase III randomized controlled trials

The aim of this meta-analysis was to summarize the efficacy and safety of bevacizumab in the treatment of ovarian cancer. We sought to identify randomised controlled trials (RCTs) by searching PubMed and Web of Science. Outcomes were objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and adverse events. Four studies with 4,246 patients were included. Combination of bevacizumab and chemotherapy resulted in a statistically significant improvement in ORR (OR 2.165, 95 % CI 1.511-3.103) and in PFS (HR 0.691, 95 % CI 0.517-0.865), compared with chemotherapy alone. There was no evidence of a significant improvement in OS (HR 0.934, 95 % CI 0.826-1.041). It also had significantly increased risk of gastrointestinal events (OR 2.743, 95 % CI 1.580-4.763; P < 0.001), hypertension (OR 4.630, 95 % CI 3.737 to 5.737; P < 0.001), proteinuria (OR 4.872, 95 % CI 2.617-9.069; P < 0.001), and arterial thromboembolism (OR 1.994, 95 % CI 1.210-3.286; P = 0.007). This meta-analysis suggests that the addition of bevacizumab to chemotherapy offers meaningful improvement in objective response rate and progression-free survival in ovarian cancer treatment, but does not benefit overall survival. It also significantly increased the occurrence of gastrointestinal events, hypertension, proteinuria, and arterial thromboembolism.

Letrozole in advanced breast cancer: the PO25 trial

Tamoxifen has been a standard first-line endocrine therapy for post-menopausal women with hormone-responsive advanced breast cancer, but more than half of patients fail to respond and time to progression is less than 12 months in responders. The third-generation aromatase inhibitors were developed to provide more effective alternatives to tamoxifen. In the Femara Study PO25, post-menopausal women with advanced breast cancer were randomized to receive letrozole 2.5 mg (n = 453) or tamoxifen 20 mg (n = 454) given orally daily until progressive disease occurred. Patients were permitted to cross over to the other treatment at progression. In the primary efficacy analysis, median time to progression (TTP) was significantly longer with letrozole than with tamoxifen (9.4 months vs. 6.0 months, respectively; P < 0.0001). The objective response rate (ORR) was significantly higher for letrozole than for tamoxifen (32% vs. 21%; P = 0.0002). Prospectively planned analyses of the intent-to-treat population showed that letrozole significantly improved overall survival (OS) compared with tamoxifen over the first 24 months of the trial. An exploratory analysis of patients, who did not cross over, indicated a median OS benefit of 14 months for letrozole compared with tamoxifen. Letrozole is the only third-generation aromatase inhibitor that has demonstrated significant improvements in ORR, TTP, and early OS.