实验性靶向治疗或可克服肺癌克唑替尼抗性（辉瑞公司的PF-06463922)

Targeted Investigational Therapy Has Potential to Overcome Crizotinib Resistance in LungCancers
实验性靶向治疗或可克服肺癌克唑替尼抗性
http://www.aacr.org/home/public- ... he-news.aspx?d=3181
PF-06463922 was found to potently inhibit theactivity of ALK and all eight of the mutant forms of ALK known to cause critzotinib resistance in lung cancer and inhibited the growth of tumors harboring crizotinib-resistant ALK mutants.
研究发现PF-06463922不仅可抑制ALK及8种ALK突变体的活性，而且能够抑制含有这几种ALK突变体的肿瘤生长。已知这8种ALK突变体正是引起肺癌对克唑替尼耐药的原因。
A significant number of lung cancer patientswill develop brain metastasis, and PF-06463922 was found to readily enter the brains of mice, rats, and dogs.
肺癌患者中有相当一部分会发生癌症脑转移，而PF-06463922已被发现可轻易进入小鼠、大鼠及狗的脑组织中。
The investigational agent had antitumor effects in two mouse models of cancers driven by ROS1 gene abnormalities, suggesting that it has potential as a treatment for this subgroup of cancers.
该试验药物在两个由ROS1基因异常驱动的癌症小鼠模型中显示出抗肿瘤作用，这表明它有潜力成为该癌症亚组的治疗药物。
The investigational drug PF-06463922 may have the potential to become a new treatment option for patients who have lungcancer harboring abnormalities in the ALK gene, according to preclinical results (Abstracts A277, PR10/B107, and C253) presented at the AACR-NCI-EORTCInternational Conference on Molecular Targets and Cancer Therapeutics, held October 19 to 23 in Boston.
根据10月19日在波士顿召开的AACR-NCI-EORTC分子靶向和癌症治疗国际会议上发表的临床前试验结果（摘要A277，PR10/B107，and C253），试验药物PF-06463922有潜力成为ALK基因异常肺癌患者的新治疗选择。
Crizotinib Resistance a Major Challenge
克唑替尼耐药：一项重大挑战
About 3% to 5% of lung cancers harbor ALKmutations, and the U.S. Food and Drug Administration approved the ALK inhibitor crizotinib (Xalkori) in August 2011 for the treatment of patients who have these lung cancers. Although robust responses to crizotinib have been observed for lung cancers harboring ALK gene abnormalities, the majority eventually become resistant to the effects of the drug. In many cases, resistance arises because of genetic mutations in ALK.
约有3%至5%的肺癌含有ALK基因突变，美国食品药品监督管理局于2011年8月批准了ALK抑制剂克唑替尼（Xalkori）来治疗这些肺癌患者。虽然ALK基因异常的肺癌对克唑替尼有强烈的反应，但是大多数最终都会对克唑替尼产生耐药。在许多病例中，耐药性的产生是由于ALK的基因突变。
“Resistance to targeted therapies such as crizotinib is a major challenge when treating patients with cancer,” said Tod Smeal, PhD, Associate Research Fellow in the Oncology Research Unit at Pfizer,Inc, in San Diego. “Our goal is to take advantage of everything we have learned about designing drugs that target kinases like ALK and the ways in which lung cancers become resistant to crizotinib to develop the best next-generation ALK inhibitor we can.
在圣地亚哥辉瑞制药公司肿瘤研究部的助理研究员，Tod Smeal博士称：“在治疗癌症患者时，对靶向治疗药物例如克唑替尼产生耐药性是一项重大的挑战，我们的目标是尽我们所能、利用一切我们所知的关于设计激酶如ALK靶向药物以及肺癌如何对克唑替尼产生耐药性，来开发最好的下一代ALK抑制剂。”
“Our preclinical studies suggest that we are making progress toward achieving our goal: PF-06463922 has potent ALK-inhibiting activity, it is capable of inhibiting all the crizotinib-resistant ALK mutantsso far detected in patients, and it can efficiently access the brain. We are excited about these preclinical results and very hopeful that they will translate into meaningful responses in the clinic.”
“我们的临床前研究表明我们正向目标前进着：PF-06463922具有较强的ALK抑制活性，到目前为止患者体内检测到的所有耐克唑替尼的ALK突变体，它都能够抑制，而且它还能有效地进入大脑。我们很高兴看到这些临床前研究结果，并且非常希望他们可以转化为临床实践中有意义的结果。”
PotentBrain-Penetrating ALK Inhibitor
有效的脑穿透性ALK抑制剂
After designing PF-06463922, Dr. Smeal and colleagues first showed in cell assays that it potently inhibited the activity of ALK and all eight of the mutant forms of ALK known to cause resistance to crizotinib in patients with lung cancer. They then showed that PF-06463922 inhibited the growth of tumors harboring three of the crizotinib-resistant ALK mutants, including the most resistant ALK mutant, G1202R, in mice.
PF-06463922的设计完成后，Smeal博士和同事们首先在细胞实验中证实它可有效抑制ALK及导致肺癌患者克唑替尼抗性的8种ALK突变体的活性。之后，他们又在小鼠中证实PF-06463922可抑制含有三种抗克唑替尼的ALK突变型肿瘤的生长，其中包括G1202R这一最常见的ALK耐药性突变。
Further analysis indicated that PF-06463922 readily entered the brains of mice, rats, and dogs. In mice, levels of PF-06463922 in the brain were 20% to 30% of levels of PF-06463922 in the blood.This is potentially clinically relevant because a significant number of lung cancer patients will develop brain metastasis during the course of their disease, according to Dr. Smeal. However, he noted that it will be important to see if these results in animals hold true in humans.
进一步分析表明，PF-06463922可轻易进入小鼠、大鼠及狗的脑组织。在小鼠中，PF-06463922在脑中的浓度为血浆中浓度的20%至30%。据Smeal博士称，肺癌患者中有相当一部分会发生脑转移，因此PF-06463922易进入脑组织的特点具有潜在的临床意义。但是他也指出，更重要的是这些在动物中实现的结果也同样能够在人类中实现。
Dr. Smeal and colleagues also found that PF-06463922 potently inhibited the protein ROS1, a close relative of ALK recently implicated in a number of cancer types, including some lung and brain cancers. Further, the investigational agent had antitumor effects in two mouse models of cancers driven by ROS1 gene abnormalities, leading the researchers to suggest that PF-06463922 has potential as a treatment for this subgroup of cancers, in addition to its promise as a new treatment for ALK-driven cancers.
Smeal博士和同事们还发现PF-06463922可有效抑制蛋白ROS1，该蛋白与ALK密切相关，最近被证实与多种癌症相关，包括一些肺癌和脑癌。此外，除了可能治疗ALK驱动型肺癌的，该试验药物在两个由ROS1基因异常驱动的癌症小鼠模型中也显示出抗肿瘤作用，使得研究者们建议它有潜力成为该癌症亚组的治疗药物。
Dr. Smeal is an employee of Pfizer, Inc, whichfunded the study.
Smeal博士为资助本项研究的辉瑞制药公司的雇员。

全球肿瘤快讯      第99100期
波士顿举行的国际分子靶向及癌症治疗策略大学上公布的临床前研究显示，目前试验药物PF-06463922有可能成为ALK基因异常的肺癌患者新的治疗选择。
克唑替尼耐药：一个重大挑战
约3%-5%的肺癌患者含有ALK突变，美国商品与药品监督局在2011年8月批准ALK抑制剂克唑替尼用于含有ALK突变的肺癌患者的治疗。然而，尽管多数含有ALK基因异常的肺癌患者克唑替尼治疗有效，但大部分患者最终对该药物产生耐药，多数情况下，耐药是由于ALK基因突变造成的。圣地亚哥辉瑞公司肿瘤研究部的副研究员托德斯米尔指出，靶向药物耐药是癌症患者治疗的一个巨大挑战，我们的目标是利用我们所学过的关于如何设计作用于激酶（如ALK）的药物的方法以及我们所知道的肺癌对克唑替尼耐药的所有途径，来研究最佳的新一代ALK抑制剂，临床前研究显示我们已经取得一些进步：PF-06463922有潜在的ALK抑制活性，它能够抑制目前我们能检测到的所有克唑替尼耐药的ALK突变，并且能够有效的进入脑组织。这些临床前研究结果令人兴奋，我们非常期待其能转化到临床应用中。
强力穿透脑屏障的ALK抑制
在设计出PF-06463922后，斯米尔医生和他的同事首先在细胞实验中发现它能够抑制ALK，以及所有8种已知的可引起肺癌患者对克唑替尼耐药的ALK突变形式的活性。随后他们发现PF-06463922能够抑制含有三种克唑替尼耐药的ALK突变的肿瘤细胞的生长，包括在小鼠身上耐药性最强的G1202R突变。进一步研究显示PF-06463922能够很容易通过小鼠、大鼠和狗的脑组织。在小鼠身上，PF-06463922在脑组织中的浓度是血液浓度的20%-30%。这有可能与药物的临床疗效相关，因为相当一部分肺癌患者在疾病过程中会发生脑转移，然而，非常重要的一点是这些在动物实验中的结果能否在人体中重复。斯米尔医生和他的同事发现PF-06463922能够抑制ROS1蛋白，它是一种最近在多种癌症类型中，包括肺癌和脑肿瘤，发现的与ALK密切相关的蛋白。此外，在两个由ROS1基因异常导致的癌症小鼠模型中，该药物均发挥了抗肿瘤疗效，提示研究者们PF-06463922除了可能对ALK驱动的癌症有效外，有可能对这部分癌症患者亦有效。

Abstract Number: A277
Presenter: Tod Smeal, Ph.D.

Title: PF-06463922, a novel ROS1/ALK inhibitor, demonstrates sub-nanomolar potency against oncogenic ROS1 fusions and capable of blocking the resistant ROS1G2032R mutant in preclinical tumor models

Authors: Helen Y. Zou, Lars R. Engstrom, Qiuhua Li, Melissa West Lu, Ruth Wei Tang, Hui Wang, Konstantinos Tsaparikos, Sergei Timofeevski, Justine Lam, Shinji Yamazaki, Wenyue Hu, Hovhannes Gukasyan, Nathan Lee, Ted W. Johnson, Valeria Fantin, Tod Smeal. Pfizer, Inc., San Diego, CA

The oncogenic ROS1 gene fusion (Fig-ROS1) was first identified in glioblastoma cells over two decades ago. Recently, ROS1 gene rearrangements were further discovered in a variety of human cancers, including lung adenocarcinoma, cholangiocarcinoma, ovarian cancer, gastric adenocarcinoma, colorectal cancer, inflammatory myofibroblastic tumor, angiosarcoma, and epithelioid hemangioendothelioma, providing additional evidence for ROS1 as an attractive cancer target. The 1st generation Met/ALK/ROS1 inhibitor XALKORI ® (crizotinib) has demonstrated promising clinical response in ROS1 fusion positive NSCLC. But similar to what was seen with acquired ALK secondary resistant mutations in XALKORI refractory patients, a ROS1 kinase domain mutant--ROS1G2032R has been identified in a ROS1 positive NSCLC patient who developed resistance to XALKORI. Therefore, there is an urgent need to develop agents that can overcome this type of resistance.

PF-06463922 is a novel, orally available, ATP-competitive small molecule inhibitor of ROS1/ALK with exquisite potency against ROS1 kinase. PF-06463922 inhibited the catalytic activity of recombinant ROS1 with a mean Ki of < 0.005 nM, and inhibited ROS1 autophosphorylation at IC50 values ranging from 0.1 nM to 1 nM cross a panel of cell lines harboring oncogenic ROS1 fusion variants including CD74-ROS1, SLC34A2-ROS1 and Fig-ROS1. PF-06463922 also inhibited cell proliferation and induced cell apoptosis at sub- to low-nanomolar concentrations in the HCC78 human NSCLC cells harboring SLC34A2-ROS1 fusions and the BaF3-CD74-ROS1 cells expressing human CD74-ROS1. In the BaF3 cells engineered to express the XALKORI resistant CD74-ROS1G2032R mutant, PF-06463922 demonstrated nanomolar potency against either ROS1G2032R cellular activity or cell proliferation. In vivo, PF-06463922 demonstrated marked cytoreductive antitumor efficacy at low nanomolar concentration in the NIH3T3 xenograft models expressing human CD74-ROS1 and Fig-ROS1. The antitumor efficacy of PF-06463922 was dose dependent and strongly correlated to inhibition in ROS1 phosphorylation and the downstream signaling molecules pSHP1, pSHP2 and pErk1/2, as well as inhibition of the cell cycle protein Cyclin D1 in tumors. To our knowledge, PF-06463922 is the first reported ROS1 inhibitor that is capable of blocking the resistant ROS1G2032R mutant at predicted pharmacologically relevant concentrations. Our data indicate that PF-06463922 has great potential for treating ROS1 fusion positive cancers including those from patients who relapsed from XALKORI therapy due to acquired ROS1G2032R mutation.

Abstract Number: PR10/B107
Presenter: Tod Smeal, Ph.D.

Title: Is CNS availability for oncology a no-brainer? Discovery of PF-06463922, a novel small molecule inhibitor of ALK/ROS1 with pre-clinical brain availability and broad spectrum potency against ALK-resistant mutations

Authors: Ted W. Johnson, Simon Bailey, Benjamin J. Burke, Michael R. Collins, J. Jean Cui, Judy Deal, Ya-Li Deng, Martin P. Edwards, Mingying He, Jacqui Hoffman, Robert L. Hoffman, Qinhua Huang, Robert S. Kania, Phuong Le, Michele McTigue, Cynthia L. Palmer, Paul F. Richardson, Neal W. Sach, Graham L. Smith, Lars Engstrom, Wenyue Hu, Hieu Lam, Justine L. Lam, Tod Smeal, Helen Y. Zou. Pfizer, Inc., San Diego, CA

Oncogenic fusions of Anaplastic Lymphoma Kinase (ALK) define a subset of human lung adenocarcinoma. The 1st generation ALK inhibitor crizotinib demonstrated impressive clinical benefit in ALK-fusion positive lung cancers and was approved by the FDA for the treatment of ALK-fusion positive NSCLC in 2011. However, as seen with most kinase inhibitors, patients treated with crizotinib eventually develop resistance to therapy. Acquired ALK kinase domain mutations and disease progression in the central nervous system (CNS) are reported as main contributors to patient relapse after ALK inhibitor therapy. Preclinically, crizotinib lacks significant brain penetration and does not potently inhibit activity of ALK kinase domain mutants, so a drug discovery program was initiated aimed to develop a second generation ALK inhibitor that is more potent than existing ALK inhibitors, capable of inhibiting the resistant ALK mutants and penetrating the blood-brain-barrier. These objectives present a considerable challenge in kinase inhibitor chemical space.

Here we report that PF-06463922, a novel small molecule ATP-competitive inhibitor of ALK/ROS1, showed exquisite potencies against non-mutant ALK (Ki <0.2 nM; cell IC50 ~2 nM) and ROS1 kinase (Ki <0.005 nM; cell IC50 ~0.2 nM), and demonstrated low nanomolar inhibitory activity against a panel of ALK kinase domain mutants representing all of the patient crizotinib resistant mutations reported to date. The more commonly reported L1196M gatekeeper mutant shows significant sensitivity to PF-06463922 (Ki 0.7 nM; cell IC50 16 nM). PF-06463922 is also very selective, and showed >100 fold kinase selectivity against 95% of the kinases tested in a 207 recombinant kinase panel.

Specific design considerations were developed leading to novel ATP-competitive kinase inhibitors with desired low efflux in cell lines over-expressing p-glycoprotein and breast cancer resistance protein, providing excellent blood-brain-barrier and cell penetration properties. Efforts to optimize ligand efficiency and lipophilic efficiency leveraging structure based drug design techniques led to ligands with overlapping broad spectrum potency and low efflux. Single and repeat dose preclinical rat in vivo studies of PF-06463922 demonstrated excellent oral bioavailability and CNS availability with free brain exposure approximately 30% of free plasma levels. In addition, CNS-directed safety studies showed no adverse events at predicted efficacious concentrations. It is anticipated that PF-06463922 with its potent activities on non-mutant ALK , ALK kinase domain mutations and CNS metastases would provide great promise for patients with ALK and ROS1 positive cancers.

Abstract Number: C253
Presenter: Tod Smeal, Ph.D.

Title: PF-06463922, a novel brain-penetrating small molecule inhibitor of ALK/ROS1 with potent activity against a broad spectrum of ALK resistant mutations in preclinical models in vitro and in vivo

Authors: Helen Y. Zou, Lars R. Engstrom, Qiuhua Li, Melissa West Lu, Ruth Wei Tang, Hui Wang, Konstantinos Tsaparikos, Jinwei Wang, Sergei Timofeevski, Dac M. Dinh, Hieu Lam, Justine Lam, Shinji Yamazaki, Wenyue Hu, Timothy Affolter, Patrick B. Lappin, Hovhannes Gukasyan, Nathan Lee, Jennifer M. Tursi, Ted W. Johnson, Valeria Fantin, Tod Smeal. Pfizer, Inc., San Diego, CA

Oncogenic fusions of Anaplastic Lymphoma Kinase (ALK) define a subset of human lung adenocarcinomas. The 1st generation ALK inhibitor XALKORI &#174; (crizotinib) demonstrated impressive clinical benefit in ALK-fusion positive lung cancers and was approved by the FDA for the treatment of ALK-fusion positive NSCLC in 2011. However, as seen with most kinase inhibitors, patients treated with XALKORI eventually developed resistance to therapy. Acquired ALK kinase domain mutations and brain metastases are significant contributors to the relapse after XALKORI therapy. To date, multiple types of ALK kinase domain mutations have been identified in XALKORI refractory patients including ALKG1269A, ALKL1196M, ALKC1156Y, ALKL1152R, ALKF1174L, ALKS1206Y, ALK1151Tins and ALKG1202R, accounting for about 1/3 of patient samples tested. Currently, a number of 2nd generation ALK inhibitors are under development aiming to overcome XALKORI resistant mutations. Even though in preclinical models, some ALK mutants such as ALKG1202R and ALK1151Tins confer high-levels of resistance to almost all of the 2nd generation ALK inhibitors tested.

Here we report PF-06463922, a novel ATP competitive small molecule inhibitor of ALK/ROS1, with potent and selective inhibitory activity against all known acquired XALKORI resistant mutations identified in patients. PF-06463922 is also capable of penetrating the blood brain barrier in preclinical animal models. In vitro, PF-06463922 demonstrated potent inhibition in catalytic activities of ALK and 8 different ALK mutant kinases in recombinant enzyme and cell based assays (cell IC50s = 1 to 65 nM). PF-06463922 also showed potent growth inhibitory activity and induced apoptosis in the NSCLC cells harboring either non-mutant ALK or mutant ALK fusions (IC50s = 1 to 30 nM). In vivo, PF-06463922 demonstrated marked cytoreductive activity in mice bearing tumor xenografts that express EML4-ALK, EML4-ALKL1196M, EML4-ALKG1269A, EML4-ALKG1202R or NPM-ALK at low nM free plasma concentrations. These effects were associated with significant inhibition in cellular Ki67 and increased cleaved-caspase3 levels in tumors. In addition, PF-06463922 achieved brain exposure of 20-30% of its plasma levels in mice, and significantly regressed the brain tumors and prolonged survival of mice bearing orthotopic EML4-ALK and EML4-ALKL1196M positive brain tumor implants. The antitumor efficacy of PF-06463922 was dose dependent and strongly correlated with inhibition of ALK phosphorylation and downstream signaling. Our data indicate that PF-06463922 is the most potent ALK inhibitor reported to date (to our knowledge, against both non-mutant or mutant ALK in cell assays), and it demonstrates great potential for treating ALK fusion positive cancers including patients who relapsed from XALKORI therapy due to various ALK kinase domain mutations and/or brain metastases.

好消息，关注中

吃克药的有福了

太好了

希望这种药能早日临床试验！！！

期待临床

好消息，期待中