Back to Authors

Untch, Michael

https://orcid.org/0000-0002-1233-1267

Mayo Clinic

Helios Hospital Berlin-Buch

Citations 19

Abstract PD1-02: Cancer predisposition genes in metastatic breast cancer – Association with metastatic pattern, prognosis, patient and tumor characteristics
Fasching, PA, Hart, SN, Polley, EC, Lee, KY, Gnanolivu, RD, Lilyquist, Jenna , Hartkopf, AD, Taran, FA, Janni, Wolfgang , Hadji, Peyman , Tesch, Hans , Haeberle, Lothar, Ettl, Johannes , Lux, MP, Lueftner, Diana, Müller, Volkmar , Beckmann, MW, Belleville, Erik, Kolberg, H-C, Fehm, TN, Overkamp, Friedrich , Wallwiener, D. , Brucker, SY, Schneeweiß, Andreas , Hu, C, Wallwiener, Markus , Wimberger, Pauline , Untch, Michael , Couch, Fergus J.

Cancer Research | February 15, 2018 | Volume: 78 | Issue: 4_Supplement | Pages: PD1-02-PD1-02

10.1158/1538-7445.sabcs17-pd1-02 Get It

Abstract Background New treatment strategies for metastatic breast cancer (mBC) are mainly driven by therapies against specific targets. BRCA mutations are one of the few established actionable targets, with PARP-Inhibitors and Platinum showing high efficacy in mBC. Hereditary cancer testing panels are now broadly used for identification of individuals with BRCA1/2 mutations who may benefit from these therapies. Many of these panels also contain other predisposition genes involved in BRCA-related DNA repair pathways, but the clinical relevance of mutations in these genes remain unclear. The aim of this study was to describe the mutation rates of BRCA1/2 and panel-based predisposition genes, and the associated clinical characteristics of individuals with these mutations, in a prospective cohort of mBC patients. Methods The PRAEGNANT mBC registry (NCT02338167) is a prospective registry for metastatic breast cancer patients with a focus on molecular biomarkers. Patients receiving any therapeutic regimen are eligible for this registry. Germline DNA was collected at study entry and genotyped for 37 cancer predisposition genes including BRCA1 and BRCA2. The frequency of mutations in each gene was determined, and associations between mutations and patient and tumor characteristics, metastatic pattern, and overall survival were assessed. Results Mutations in established high (odds ratio (OR)>5.0) and moderate risk (OR>2.0) breast cancer genes (BRCA1/2, PALB2, CHEK2, ATM, RAD51D, BARD1, and MSH6) were seen in 123 of 1462 tested patients with mBC (8.4%). BRCA1 and BRCA2 mutations were seen in 1.4% and 2.9% of patients respectively. Most frequently mutated non-BRCA panel genes were CHEK2, PALB2 and ATM with 2.8%, 0.8% and 0.6% of patients. Mutation frequency varied with regard to patients who developed brain metastases, visceral metastases or bone only metastases. BRCA1 or BRCA2 mutations were seen frequently in patients with brain (5.3%) or visceral metastases (5.2%), but were present in only 2.5% patients with bone only metastases and 1.5% of patients with lesions in other locations. Panel genes were equally distributed among all metastatic patients. PALB2 mutations (n=11) were only seen in patients with brain (1.9%) and visceral metastases (0.9%), but not in patients with bone metastases or other locations. 36.4% (N=4) of all patients with PALB2 mutations developing a brain metastasis. When adjusted for other mBC prognostic factors, a mutation (all genes) was associated with an unfavorable prognosis (HR: 1.50; 95%CI: 1.04 to 2.30, p=0.03). Mutation frequencies were similar according to therapy lines. All other associations with molecular subtypes and risk factors were similar to primary breast cancer cases. Conclusion Mutations in high and moderate risk breast cancer genes were frequent in metastatic breast cancer patients. The frequency was substantially higher than the 4 to 5% mutation frequency observed among unselected primary breast cancer patients, but is consistent with recent results from studies of metastatic prostate cancer patients. Patients with brain and visceral metastases had the highest BRCA mutation rates. Results suggested that PALB2 mutations may be more frequent in patients with brain metastases. Citation Format: Fasching PA, Hu C, Hart SN, Polley EC, Lee KY, Gnanolivu RD, Lilyquist J, Hartkopf AD, Taran FA, Janni W, Hadji P, Tesch H, Haeberle L, Ettl J, Lux MP, Lueftner D, Wallwiener M, Mueller V, Beckmann MW, Belleville E, Wimberger P, Untch M, Kolberg H-C, Fehm TN, Overkamp F, Wallwiener D, Brucker SY, Schneeweiss A, Couch F. Cancer predisposition genes in metastatic breast cancer – Association with metastatic pattern, prognosis, patient and tumor characteristics [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 PD1-02.
First results from the phase III ALTTO trial (BIG 2-06; NCCTG [Alliance] N063D) comparing one year of anti-HER2 therapy with lapatinib alone (L), trastuzumab alone (T), their sequence (T→L), or their combination (T+L) in the adjuvant treatment of HER2-posi
Piccart, Martine , Holmes, Andrew , Baselga, José , Viale, Giuseppe , Zujewski, Jo Anne , Goldhirsch, Aron, Jackisch, Christian , Láng, István, Smith, Ian E., Boyle, Frances , Gelber, Richard D. , Perez, Edith A. , Azambuja, Evandro de , Dueck, Amylou C. , Zujewski, Jo Anne , Santillana, Sergio , Pritchard, Kathleen I. , Wolff, Antonio C. , Untch, Michael , Xu, Binghe , Gómez, Henry

Journal of Clinical Oncology | February 24, 2017 | Volume: 32 | Issue: 18_suppl | Pages: LBA4-LBA4

10.1200/jco.2014.32.18_suppl.lba4 Get It

LBA4 Background: Lapatinib (L) is a HER1-HER2 tyrosine kinase inhibitor. The Adjuvant Lapatinib and/or Trastuzumab Treatment Optimisation (ALTTO) Trial is a randomised, phase III trial comparing 3 oral L-containing regimens with T, each given for 1 year. Methods: From June 2007 to July 2011, 8381 patients (pts) were randomised from 946 sites in 44 countries to receive either L+T, T→L, L, or T. Anti-HER2 therapy was initiated after completing all chemotherapy (N=4613), concurrently with a taxane following anthracycline (N=3337), or concurrently with a non-anthracycline, platinum-containing regimen (N=431). The L arm was closed in Aug 2011 for futility and is not presented. The primary endpoint is invasive disease-free survival (DFS). L+T vs. T is tested for superiority and T→L vs. T is tested for non-inferiority at 1.11 margin. P≤0.025 is required for statistical significance. 850 DFS events in the L+T vs. T comparison would provide 80% power to detect a true hazard ratio (HR) of 0.80 with experiment-wide alpha=0.05. The current analysis was planned to occur either after observing these 850 events or at 4.5 yrs median follow up (MFU). Results: Pt and disease characteristics were well balanced. 40% were node-negative and 57% were hormone receptor positive. Only 555 DFS events for the L+T vs. T comparison were observed at 4.5 years MFU. HR for DFS was 0.84 (97.5% CI, 0.70-1.02; P=0.048; 4-yr DFS%=88% vs. 86%) for L+T vs. T and 0.93 (97.5% CI, 0.76-1.13; non-inferiority P=0.044; 4-yr DFS%=87% vs. 86%) for T→L vs. T. Diarrhoea (75% vs. 20%), rash (55% vs. 20%) and hepatobiliary (23% vs. 16%) adverse events were more frequent in L+T vs. T. Primary cardiac endpoints were infrequent (<1%) in all arms. Conclusions: L+T has lower risk of a DFS event compared with T, and T→L appeared non-inferior to T, but neither finding was statistically significant. The first DFS results of dual HER2 blockade in the adjuvant ALTTO at 4.5 years MFU are unexpected considering the effect shown by doubling the pCR rate with L+T vs. T in the NeoALLTO trial. Follow up continues. Clinical trial information: NCT00490139.
Abstract S5-06: BRCA mutations, therapy response and prognosis in the neoadjuvant GeparQuinto study
Fasching, PA, Loibl, Sibylle , Eidtmann, Holger, Tesch, Hans , Hilfrich, J., Schem, Christian , Rezai, Mahdi , Costa, SD , Fehm, TN, Huober, Jens , Liedtke, C, Müller, Volkmar , Nekljudova, Valentina , Weber, Karsten E. , Rack, Brigitte , Rübner, Matthias, Wang, L, Ingle, JN, Weinshilboum, RM, Minckwitz, Gϋnter von, Untch, Michael , Gerber, B. , Blohmer, Jens‐Uwe , Couch, Fergus J.

Cancer Research | May 20, 2016 | Volume: 76 | Issue: 4_Supplement | Pages: S5-06-S5-06

10.1158/1538-7445.sabcs15-s5-06 Get It

Abstract Background: Mutations in BRCA1 and BRCA2 influence the molecular pathogenesis of breast cancer. However, little is known about the association between mutations, response to therapy, and prognosis. We therefore analysed these associations in triple negative breast cancer (TNBC) patients in the neoadjuvant GeparQuinto Study. Methods: The GeparQuinto study recruited 1956 patients with HER2 negative disease including a prespecified group of 671 TNBC patients with untreated breast cancer. Patients were randomized to receive four cycles EC (90/600 mg/m2; q3w) followed by four cycles docetaxel (100 mg/m2; q3w), with or without bevacizumab (15 mg/kg). Here we present the analysis for both randomization arms combined. Sufficient blood was available of 482 TNBC patients. BRCA1 and BRCA2 genotyping was successful in 469 patients with available germline DNA and was conducted by SureSelect custom capture and sequencing on HiSeq 2500. Mutation status was correlated with pathological complete response rates (pCR) and disease free survival (DFS). Results: A total of 74 (15.8%) mutations in BRCA1 (n=61) and BRCA2 (n=13) were detected after initial sequencing. A pCR (ypT0/ypN0) was observed in 50% (n=37) of mutation carriers but only 31.1% (n=123) of patients without mutations (p=0.002). Similar results were observed for pCR (pT0is/pN0) (52.7% vs. 36.5%; p=0.010). pCR (ypT0/ypN0) was predictive of disease free survival (DFS) in all patients (Hazard Ratio, HR=0.23; 95%CI: 0.15-0.37; p&lt;0.001) and in patients without BRCA mutations pCR (ypT0/ypN0) (HR= 0.20; 95%CI: 0.11-0.34; p&lt;0.001). However in mutation carriers this effect was reduced (HR=0.48; 95%CI: 0.18 1.27; p=0.129). Conclusion: TNBC Patients with BRCA mutations showed a higher frequency of pCR than patients without BRCA mutations after treatment with epirubicin, cyclophosphamide and docetaxel (+/ bevacizumab), suggesting that BRCA mutations may influence pCR in response to treatment regimens that do not include platin chemotherapy. pCR as a surrogate marker for DFS was also confirmed in patients without BRCA mutations. In addition, the effect of pCR on prognosis seemed to be smaller among the mutation carriers, although the number of mutation carriers was too low to test for differences between mutation carriers and wildtype patients. The project has partly been funded within NIH-NIGMS U19 GM61388 and the Breast Cancer Research Foundation. Citation Format: Fasching PA, Loibl S, Eidtmann H, Tesch H, Untch M, Hilfrich J, Schem C, Rezai M, Gerber B, Costa SD, Blohmer JU, Fehm TN, Huober J, Liedtke C, Müller V, Nekljudova V, Weber K, Rack B, Rübner M, Wang L, Ingle JN, Weinshilboum RM, von Minckwitz G, Couch F. BRCA mutations, therapy response and prognosis in the neoadjuvant GeparQuinto study. [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 S5-06.
Abstract PD5-07: The impact of early lapatinib-induced rash on disease-free and overall survival in patients treated within the ALTTO phase III randomized trial
Azim, HA, Sonnenblick, Amir , Agbor‐Tarh, Dominique, Bradbury, I, Daly, F., Huang, Yinan , Dueck, A. C. , Jackisch, Christian , Láng, István, Boyle, Frances , Perez, Edith A. , Piccart, Martine , Pritchard, Kathleen I. , Wolff, Antonio C. , Untch, Michael , Smith, Ian , Xu, Binghe , Gómez, Henry , Azambuja, Evandro de

Cancer Research | May 20, 2016 | Volume: 76 | Issue: 4_Supplement | Pages: PD5-07-PD5-07

10.1158/1538-7445.sabcs15-pd5-07 Get It

Abstract Background: We have previously shown in a phase III neoadjuvant trial that early development of lapatinib-induced rash (i.e. within 6 weeks after lapatinib initiation) is independently associated with a higher chance of obtaining a pathological complete response (Azim et al; JCO 2013). In the current study, we aimed to investigate whether early lapatinib-induced rash is associated with improved survival in the context of a large phase III adjuvant trial. Methods: This analysis is based on the ALTTO trial (BIG 2-06, Alliance N063D), in which patients with HER2-positive early breast cancer were randomized to adjuvant trastuzumab, lapatinib, their sequence or their combination for a total duration of 1 year. In this sub-study, we evaluated whether the development of rash (any grade) within 6 weeks of lapatinib initiation was associated with disease-free (DFS) and overall survival (OS). All analyses were tested in a multivariate model adjusted for treatment arm, treatment completion and trial stratification factors. Results: A total of 6,098 lapatinib-treated patients were included in the current analysis; of whom 2,006 patients (32.9%) developed early lapatinib-induced rash, 1,025 (16.8%) developed rash after 6 weeks and 3,067 (50.3%) did not develop rash. No differences in patient characteristics were observed between the three groups apart from a higher frequency of younger patients (≤ 50) in the early rash group (54% vs. 47% and 44%, p&lt;0.0001). At a median follow-up of 4.5 years, 876 (14.37%) and 377 (6.18%) patients in the lapatinib containing arms experienced a DFS and OS event, respectively. In a multivariate analysis confined to patients randomized to the lapatinib containing arms, the development of early rash was associated with improved DFS (HR: 0.80; 95%CI: 0.69-0.93, p=0.004) and OS (HR: 0.61; 95%CI: 0.48 - 0.78, p&lt;0.001) compared to patients who did not develop early rash, with no interaction according to patient's age (p=0.9). No significant association was observed between the development of rash after 6 weeks of lapatinib initiation and survival. Compared to patients randomized to the trastuzumab alone arm (n=2,076), patients who developed early rash in the sequence (n=580) or combination (n=704) arms of trastuzumab/lapatinib had superior DFS (Sequence: HR 0.75 [95% CI: 0.58 – 0.98], p=0.034; Combination: HR 0.69 [95% CI: 0.54 – 0.89], p=0.005) and OS (Sequence: HR 0.57 [95%CI: 0.36 – 0.88], p=0.012; Combination: HR 0.59 [95% CI: 0.39 – 0.89], p=0.011). On the other hand, patients randomized to the lapatinib only arm who developed early rash (n=722) still had inferior DFS (HR 1.28 [95% CI: 1.04 – 1.59], p=0.02) with no difference in OS (HR: 0.95; 95%CI: 0.67 – 1.35, p=0.79) compared to patients randomized to the trastuzumab alone arm. Conclusions: The results support our previous findings in the neoadjuvant setting that early development of skin rash within the first 6 weeks can identify patients who derive superior benefit of lapatinib treatment. Citation Format: Azim Jr HA, Sonnenblick A, Agbor-Tarh D, Bradbury I, Daly F, Huang Y, Dueck AC, Pritchard K, Wolff AC, Jackisch C, Lang I, Untch M, Smith I, Boyle F, Xu B, Gomez H, Perez E, Piccart M, de Azambuja E. The impact of early lapatinib-induced rash on disease-free and overall survival in patients treated within the ALTTO phase III randomized trial. [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 PD5-07.
Adjuvant Lapatinib and Trastuzumab for Early Human Epidermal Growth Factor Receptor 2–Positive Breast Cancer: Results From the Randomized Phase III Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization Trial
Piccart, Martine , Holmes, Eileen , Baselga, José , Azambuja, Evandro de , Dueck, Amylou C. , Viale, Giuseppe , Zujewski, Jo Anne , Goldhirsch, Aron, Armour, Alison, McCullough, Ann E. , Dolci, Stella, McFadden, Eleanor, Holmes, Andrew , Tonghua, Liu, Eidtmann, Holger, Dinh, Phuong , Cosimo, Serena Di , Tjulandin, Sergei , Im, Young‐Hyuck , Huang, Chiun‐Sheng , Wolff, Antonio C. , Jackisch, Christian , Láng, István, Boyle, Frances , Gómez, Henry , Gelber, Richard D. , Perez, Edith A. , Piccart-Gebhart, Martine, de Azambuja, Evandro, Pritchard, Kathleen I. , Holmes, Andrew P, Di Cosimo, Serena, Harbeck, Nadia , Dièras, Véronique , Hillman, David W. , Untch, Michael , Smith, Ian , Xu, Binghe , Suter, Thomas, Dueck, A. C. , Zujewski, Jo Anne , Tonghua, Liu, Xu, Binghe , Suter, Thomas , Wolff, Antonio C , de Azambuja, Evandro , Huang, Chiun-Sheng

Journal of Clinical Oncology | November 23, 2015 | Volume: 34 | Issue: 10 | Pages: 1034-1042

10.1200/jco.2015.62.1797 Get It

Background Lapatinib (L) plus trastuzumab (T) improves outcomes for metastatic human epidermal growth factor 2–positive breast cancer and increases the pathologic complete response in the neoadjuvant setting, but their role as adjuvant therapy remains uncertain. Methods In the Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization trial, patients with centrally confirmed human epidermal growth factor 2–positive early breast cancer were randomly assigned to 1 year of adjuvant therapy with T, L, their sequence (T→L), or their combination (L+T). The primary end point was disease-free survival (DFS), with 850 events required for 80% power to detect a hazard ratio (HR) of 0.8 for L+T versus T. Results Between June 2007 and July 2011, 8,381 patients were enrolled. In 2011, due to futility to demonstrate noninferiority of L versus T, the L arm was closed, and patients free of disease were offered adjuvant T. A protocol modification required P ≤ .025 for the two remaining pairwise comparisons. At a protocol-specified analysis with a median follow-up of 4.5 years, a 16% reduction in the DFS hazard rate was observed with L+T compared with T (555 DFS events; HR, 0.84; 97.5% CI, 0.70 to 1.02; P = .048), and a 4% reduction was observed with T→L compared with T (HR, 0.96; 97.5% CI, 0.80 to 1.15; P = .61). L-treated patients experienced more diarrhea, cutaneous rash, and hepatic toxicity compared with T-treated patients. The incidence of cardiac toxicity was low in all treatment arms. Conclusion Adjuvant treatment that includes L did not significantly improve DFS compared with T alone and added toxicity. One year of adjuvant T remains standard of care.
Genetic variants in VEGF pathway genes in neoadjuvant breast cancer patients receiving bevacizumab: Results from the randomized phase III GeparQuinto study
Hein, Alexander , Lambrechts, Diether , Minckwitz, Gϋnter von, Häberle, Lothar , Eidtmann, Holger, Tesch, Hans , Hilfrich, J., Schem, Christian , Rezai, Mahdi , Gerber, Bernd, Costa, Serban Dan, Blohmer, Jens‐Uwe , Schwedler, Kathrin, Kittel, K., Fehm, Tanja , Kunz, Georg , Beckmann, Matthias W. , Ekici, Arif B. , Hanusch, Claus , Huober, Jens , Liedtke, Cornelia, Moisse, Matthieu , Müller, Volkmar , Nekljudova, Valentina , Peuteman, Gilian, Rack, Brigitte , Rübner, Matthias, Brussel, Thomas Van , Wang, Liewei , Weinshilboum, Richard M. , Loibl, Sibylle , Fasching, Peter A. , Lambrechts, Diether , Untch, Michael , Mau, Christine , Weinshilboum, Richard M. , Lambrechts, Diether , Hein, Alexander , Lambrechts, Diether , Ekici, Arif B , Moisse, Matthieu , Fehm, Tanja

International Journal of Cancer | June 23, 2015 | Volume: 137 | Issue: 12 | Pages: 2981-2988

10.1002/ijc.29656 Get It

Studies assessing the effect of bevacizumab (BEV) on breast cancer (BC) outcome have shown different effects on progression‐free and overall survival, suggesting that a subgroup of patients may benefit from this treatment. Unfortunately, no biomarkers exist to identify these patients. Here, we investigate whether single nucleotide polymorphisms (SNPs) in VEGF pathway genes correlate with pathological complete response (pCR) in the neoadjuvant GeparQuinto trial. HER2‐negative patients were randomized into treatment arms receiving either BEV combined with standard chemotherapy or chemotherapy alone. In a pre‐planned biomarker study, DNA was collected from 729 and 724 patients, respectively from both treatment arms, and genotyped for 125 SNPs. Logistic regression assessed interaction between individual SNPs and both treatment arms to predict pCR. Five SNPs may be associated with a better response to BEV, but none of them remained significant after correction for multiple testing. The two SNPs most strongly associated, rs833058 and rs699947, were located upstream of the VEGF‐A promoter. Odds ratios for the homozygous common, heterozygous and homozygous rare rs833058 genotypes were 2.36 (95% CI, 1.49–3.75), 1.20 (95% CI, 0.88–1.64) and 0.61 (95% CI, 0.34–1.12). Notably, some SNPs in VEGF‐A exhibited a more pronounced effect in the triple‐negative subgroup. Several SNPs in VEGF‐A may be associated with improved pCR when receiving BEV in the neoadjuvant setting. Although none of the observed effects survived correction for multiple testing, our observations are consistent with previous studies on BEV efficacy in BC. Further research is warranted to clarify the predictive value of these markers.
Analysis of Regional Timelines To Set Up a Global Phase III Clinical Trial in Breast Cancer: The Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization Experience
Azambuja, Evandro de , Bradbury, Ian , Saini, Kamal S. , Simon, Sérgio D. , Dooren, Veerle Van, Aktan, Gursel, Wolff, Antonio C. , Jackisch, Christian , Láng, István, Boyle, Frances , Baselga, José , Perez, Edith A. , Piccart, Martine , Metzger, Otto , Bines, José , Pritchard, Kathleen I. , Smith, Ian , Untch, Michael , Xu, Binghe , Wolff, Antonio C , de Azambuja, Evandro

The Oncologist | January 29, 2013 | Volume: 18 | Issue: 2 | Pages: 134-140

10.1634/theoncologist.2012-0342 Get It

Abstract Learning Objectives Discuss methods for improving the efficiency of global clinical trials. Explain the need for national regulatory authorities and collaborative cancer groups to initiate efforts to quicken the activation process in their countries. Describe the activation process of phase III studies and its complex and heterogeneous regulation across different geographic and economic regions. Purpose. This study measured the time taken for setting up the different facets of Adjuvant Lapatinib and/or Trastuzumab Treatment Optimization (ALTTO), an international phase III study being conducted in 44 participating countries. Methods. Time to regulatory authority (RA) approval, time to ethics committee/institutional review board (EC/IRB) approval, time from study approval by EC/IRB to first randomized patient, and time from first to last randomized patient were prospectively collected in the ALTTO study. Analyses were conducted by grouping countries into either geographic regions or economic classes as per the World Bank's criteria. Results. South America had a significantly longer time to RA approval (median: 236 days, range: 21–257 days) than Europe (median: 52 days, range: 0–151 days), North America (median: 26 days, range: 22–30 days), and Asia-Pacific (median: 62 days, range: 37–75 days). Upper-middle economies had longer times to RA approval (median: 123 days, range: 21–257 days) than high-income (median: 47 days, range: 0–112 days) and lower-middle income economies (median: 57 days, range: 37–62 days). No significant difference was observed for time to EC/IRB approval across the studied regions (median: 59 days, range 0–174 days). Overall, the median time from EC/IRB approval to first recruited patient was 169 days (range: 26–412 days). Conclusion. This study highlights the long time intervals required to activate a global phase III trial. Collaborative research groups, pharmaceutical industry sponsors, and regulatory authorities should analyze the current system and enter into dialogue for optimizing local policies. This would enable faster access of patients to innovative therapies and enhance the efficiency of clinical research.
Activity of the Dual Kinase Inhibitor Lapatinib (GW572016) against HER-2-Overexpressing and Trastuzumab-Treated Breast Cancer Cells
Konecny, Gottfried E. , Pegram, Mark D. , Venkatesan, Natarajan , Yang, Guorong , Rahmeh, Martina, Rusnak, David W., Spehar, Glenn, Mullin, Robert J., Keith, Barry R., Gilmer, Tona M. , Berger, Mark S., Podratz, Karl C. , Slamon, Dennis J. , Finn, Richard S. , Untch, Michael

Cancer Research | February 1, 2006 | Volume: 66 | Issue: 3 | Pages: 1630-1639

10.1158/0008-5472.can-05-1182 Get It

Abstract Lapatinib (GW572016) is a selective inhibitor of both epidermal growth factor receptor (EGFR) and HER-2 tyrosine kinases. Here, we explore the therapeutic potential of lapatinib by testing its effect on tumor cell growth in a panel of 31 characterized human breast cancer cell lines, including trastuzumab-conditioned HER-2-positive cell lines. We further characterize its activity in combination with trastuzumab and analyze whether EGFR and HER-2 expression or changes induced in the activation of EGFR, HER-2, Raf, AKT, or extracellular signal-regulated kinase (ERK) are markers of drug activity. We report that concentration-dependent antiproliferative effects of lapatinib were seen in all breast cancer cell lines tested but varied significantly between individual cell lines with up to 1,000-fold difference in the IC50s (range, 0.010-18.6 μmol/L). Response to lapatinib was significantly correlated with HER-2 expression and its ability to inhibit HER-2, Raf, AKT, and ERK phosphorylation. Long-term in vivo lapatinib studies were conducted with human breast cancer xenografts in athymic mice. Treatment over 77 days resulted in a sustained and significant reduction in xenograft volume compared with untreated controls. For the combination of lapatinib plus trastuzumab, synergistic drug interactions were observed in four different HER-2-overexpressing cell lines. Moreover, lapatinib retained significant in vitro activity against cell lines selected for long-term outgrowth (&gt;9 months) in trastuzumab-containing (100 μg/mL) culture medium. These observations provide a clear biological rationale to test lapatinib as a single agent or in combination with trastuzumab in HER-2-overexpressing breast cancer and in patients with clinical resistance to trastuzumab. (Cancer Res 2006; 66(3): 1630-9)