PDF file 70K, This table contains the IC50 values of in vitro cell survival assay for crizotinib or ceritinib in engineered EML4-ALK mutant Ba/F3 cells corresponding to Fig 4A
PDF file 135K, Figure S1 contains data about Ceritinib specificity and potency on crizotinib na?ve EML4-ALK wild-type cells. Figure S2 contains the Cell survival curves of H3122 CR1, MGH021-4 and MGH045 cells following treatment with Crizotinib or ceritinib corresponding to Fig2A. Figure S3 contains the Cell survival curves of Ba/F3 cells following treatment with Crizotinib or ceritinib corresponding to Fig4A. Figure S4 contains tumor growth curves corresponding to the Development of crizotinib resistant H2228 xenograft tumor models used in Fig 5A-D
N-substituted azaindoles were discovered as potent pan-PIM inhibitors. Lead optimization, guided by structure and focused on physico-chemical properties allowed us to solve inherent hERG and permeability liabilities, and provided compound 27, which subsequently impacted KG-1 tumor growth in a mouse model.
TGFβ is a pleiotropic cytokine that may have both tumor inhibiting and tumor promoting properties, depending on tissue and cellular context. Emerging data support a role for TGFβ in suppression of antitumor immunity. Here we show that SAR439459, a pan-TGFβ neutralizing antibody, inhibits all active isoforms of human and murine TGFβ, blocks TGFβ-mediated pSMAD signaling, and TGFβ-mediated suppression of T cells and NK cells. In vitro, SAR439459 synergized with anti-PD1 to enhance T cell responsiveness. In syngeneic tumor models, SAR439459 treatment impaired tumor growth, while the combination of SAR439459 with anti–PD-1 resulted in complete tumor regression and a prolonged antitumor immunity. Mechanistically, we found that TGFβ inhibition with PD-1 blockade augmented intratumoral CD8+ T cell proliferation, reduced exhaustion, evoked proinflammatory cytokines, and promoted tumor-specific CD8+ T cell responses. Together, these data support the hypothesis that TGFβ neutralization using SAR439459 synergizes with PD-1 blockade to promote antitumor immunity and formed the basis for the ongoing clinical investigation of SAR439459 in patients with cancer (NCT03192345).
Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase belonging to the insulin receptor superfamily. Expression of ALK in normal human tissues is only found in a subset of neural cells, however it is involved in the genesis of several cancers through genetic aberrations involving translocation of the kinase domain with multiple fusion partners (e.g., NPM-ALK in anaplastic large cell lymphoma ALCL or EML4-ALK in non-small cell lung cancer) or activating mutations in the full-length receptor resulting in ligand-independent constitutive activation (e.g., neuroblastoma). Here we are reporting the discovery of novel and selective anaplastic lymphoma kinase inhibitors from specific modifications of the 2,4-diaminopyridine core present in TAE684 and LDK378. Synthesis, structure activity relationships (SAR), absorption, distribution, metabolism, and excretion (ADME) profile, and in vivo efficacy in a mouse xenograft model of anaplastic large cell lymphoma are described.
Abstract Non–small cell lung cancers (NSCLC) harboring anaplastic lymphoma kinase (ALK) gene rearrangements invariably develop resistance to the ALK tyrosine kinase inhibitor (TKI) crizotinib. Herein, we report the first preclinical evaluation of the next-generation ALK TKI, ceritinib (LDK378), in the setting of crizotinib resistance. An interrogation of in vitro and in vivo models of acquired resistance to crizotinib, including cell lines established from biopsies of patients with crizotinib-resistant NSCLC, revealed that ceritinib potently overcomes crizotinib-resistant mutations. In particular, ceritinib effectively inhibits ALK harboring L1196M, G1269A, I1171T, and S1206Y mutations, and a cocrystal structure of ceritinib bound to ALK provides structural bases for this increased potency. However, we observed that ceritinib did not overcome two crizotinib-resistant ALK mutations, G1202R and F1174C, and one of these mutations was identified in 5 of 11 biopsies from patients with acquired resistance to ceritinib. Altogether, our results demonstrate that ceritinib can overcome crizotinib resistance, consistent with clinical data showing marked efficacy of ceritinib in patients with crizotinib-resistant disease. Significance: The second-generation ALK inhibitor ceritinib can overcome several crizotinib-resistant mutations and is potent against several in vitro and in vivo laboratory models of acquired resistance to crizotinib. These findings provide the molecular basis for the marked clinical activity of ceritinib in patients with ALK-positive NSCLC with crizotinib-resistant disease. Cancer Discov; 4(6); 662–73. ©2014 AACR. See related commentary by Ramalingam and Khuri, p. 634 This article is highlighted in the In This Issue feature, p. 621
Abstract Non-small cell lung cancers (NSCLC) harboring anaplastic lymphoma kinase (ALK) gene rearrangements are sensitive to the ALK tyrosine kinase inhibitor (TKI) crizotinib. However, these cancers invariably relapse due to the development of resistance, and approximately 1/3 of such cancers develop resistance mutations within the ALK tyrosine kinase domain. Here we report the preclinical evaluation of the next-generation ALK TKI, LDK378 in the setting of crizotinib resistance. Using EML4-ALK mutant Ba/F3 cellular models, in vivo models of acquired resistance to crizotinib, and novel cell lines established from biopsies of crizotinib-resistant NSCLC patients, we have examined the efficacy of LDK378 in crizotinib-naïve and -resistant ALK-positive cancers. These studies reveal that LDK378 is more potent than crizotinib and effectively overcomes resistance in vitro and in vivo. In particular, LDK378 inhibits ALK harboring crizotinib resistance mutations, including L1196M, G1269A, I1171T and S1206Y. Cell lines derived from crizotinib-resistant biopsies were sensitive to LDK378, including one that did not harbor an ALK resistance mutation and was also sensitive to crizotinib, suggesting that some crizotinib-resistant cancers with wildtype ALK are still sensitive to complete ALK inhibition. We observed that LDK378 did not effectively overcome two crizotinib-resistant ALK mutations, G1202R and F1174C ALK, and mutations in one of these residues was identified in 5 out of 11 biopsies from patients with acquired resistance to LDK378. Altogether our results demonstrate that LDK378 can overcome many mechanisms of crizotinib resistance, consistent with emerging clinical data showing marked efficacy of LDK378 in patients with crizotinib-resistant disease. Citation Format: Luc Friboulet, Nanxin Li, Ryohei Katayama, Christian C. Lee, Justin F. Gainor, Adam S. Crystal, Pierre-Yves Michellys, Mark M. Awad, Noriko Yanagitani, Sungjoon Kim, AnneMarie Pferdekamper, Jie Li, Shailaja Kasibhatla, Frank Sun, Xiuying Sun, Su Hua, Peter McNamara, Sidra Mahmood, Elizabeth L. Lockerman, Naoya Fujita, Makoto Nishio, Jennifer L. Harris, Alice T. Shaw, Jeffrey A. Engelman. The ALK inhibitor LDK378 overcomes crizotinib resistance in non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 957. doi:10.1158/1538-7445.AM2014-957
The synthesis, preclinical profile, and in vivo efficacy in rat xenograft models of the novel and selective anaplastic lymphoma kinase inhibitor 15b (LDK378) are described. In this initial report, preliminary structure-activity relationships (SARs) are described as well as the rational design strategy employed to overcome the development deficiencies of the first generation ALK inhibitor 4 (TAE684). Compound 15b is currently in phase 1 and phase 2 clinical trials with substantial antitumor activity being observed in ALK-positive cancer patients.
Abstract Selective RAF inhibitors have significant activity in patients with metastatic melanoma whose tumors express BRAFV600E. However, not all patients respond equally well to treatment and the duration of response is often limited to less than 6 months. LGX818 was developed with the hypothesis that a more potent inhibitor with excellent pharmacological properties would maximize the degree and duration of patient response. LGX818 is a highly potent RAF inhibitor with selective anti-proliferative and apoptotic activity in cells expressing BRAFV600E. In the A375 (BRAFV600E) human melanoma cell line LGX818 suppresses phospho-ERK (EC50 = 3 nM) leading to potent inhibition of proliferation (EC50 = 4 nM). No significant activity was observed against a panel of 100 kinases (IC50 > 900 nM) and LGX818 did not inhibit proliferation of > 400 cell lines expressing wild-type BRAF. Contributing to the high potency of LGX818 is the extremely slow off-rate from BRAFV600E which is not observed with other RAF inhibitors. In biochemical assays the dissociation half-life was >24 hours which translated into sustained target inhibition in cells following drug wash-out. Single dose PK/PD studies in human melanoma xenograft models (BRAFV600E) indicated that LGX818 treatment at oral doses as low as 6 mg/kg resulted in strong (75%) and sustained (>24 hours) decrease in phospho-MEK, even following clearance of drug from circulation. Decreases in phospho-ERK were consistent with phospho-MEK but markers of downstream transcriptional output (DUSP6 and SPRY4) appeared to provide a more sensitive measure of pathway activation. LGX818 induced tumor regression in multiple BRAF mutant human tumor xenograft models grown in immune compromised mice and rats at doses as low as 1 mg/kg. Consistent with the in vitro data, LGX818 was inactive against BRAF wild-type tumors at doses up to 300 mg/kg bid, with good tolerability and linear increase in exposure. Efficacy was also achieved in a more disease-relevant spontaneous metastatic melanoma and a model of melanoma brain metastasis. LGX818 is a potent and selective RAF kinase inhibitor with unique biochemical properties that contribute to an excellent pharmacological profile. A Phase I clinical trial in patients with BRAF mutant tumors is ongoing. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3790. doi:1538-7445.AM2012-3790
Abstract A c-MET/ALK kinase inhibitor crizotinib has demonstrated significant activity in lung cancer patients with EML4-ALK in clinical studies. However relapse (or acquired resistance) has also been reported. We have developed crizotinib resistant tumor models and used the models to evaluate the ALK inhibitor LDK378. LDK378 is a potent and selective ALK inhibitor that does not cross react with c-MET. In a mouse xenograft tumor model derived from the EML4-ALK+ lung cancer cell line NCI-H2228, LDK378 caused complete tumor regression when dosed orally at 25 mg/kg/day. After tumor bearing animals had been treated with LDK378 at 50 mg/kg/day for 14 days, remission was maintained for more than 4 months. In several NCI-H2228 tumor models that were induced to become resistant to crizotinib, LDK378 demonstrated efficacy at 50 mg/kg/day. Based on 4-wk GLP toxicology studies the drug exposure associated with this dose is predicted to be below the exposure at the MTD in humans. ALK resistance mutations reported in crizotinib relapsed patients were also found in the crizotinib resistant NCI-H2228 tumor models. The results from these preclinical studies suggest that LDK378 may be active in crizotinib-relapsed patients. A phase I clinical study of LDK378 has recently begun in both crizotinib-relapsed and crizotinib-naïve patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B232.
Abstract We recently reported a new class of allosteric inhibitors, exemplified by GNF-2, that selectively inhibit the proliferation of Bcr-Abl dependent cells. Here we demonstrate, using selection for resistant Bcr-Abl clones, site-directed mutagenesis, affinity chromatography, and steady-state kinetics, that GNF-2 inhibits Bcr-Abl kinase activity by binding to the Abl myristate binding pocket and stabilizes the auto-inhibited conformation. We demonstrate that the 2-hydroxyethyl amide analog of GNF-2, GNF-5, in combination with ATP-competitive inhibitors such as nilotinib and dasatinib can overcome the T315I “gatekeeper” mutant of Bcr-Abl which is resistant to all clinically approved Bcr-Abl inhibitors. These studies demonstrate that targeting of the Abl myristate binding site can provide an important pharmacological means to overcome mutations that cause resistance to ATP-competitive inhibitors. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B165.
A new class of water-soluble, amphiphilic star block copolymers with a large number of arms was prepared by sequential atom transfer radical polymerization (ATRP) of n-butyl methacrylate (BMA) and poly( ethylene glycol) methyl ether methacrylate (PEGMA). As the macroinitiator for the ATRP, a 2-bromoisobutyric acid functionalized fourth-generation hyperbranched polyester (Boltorn H40) was used, which allowed the preparation of star polymers that contained on average 20 diblock copolymer arms. The synthetic concept was validated by AFM experiments, which allowed direct visualization of single molecules of the multiarm star block copolymers. DSC and SAXS experiments on bulk samples suggested a microphase-separated structure, in agreement with the core-shell architecture of the polymers. SAXS experiments on aqueous solutions indicated that the star block copolymers can be regarded as unimolecular micelles composed of a PBMA core and a diffuse PPEGMA corona. The ability of the polymers to encapsulate and release hydrophobic guests was evaluated using H-1 NMR spectroscopy. In dilute aqueous solution, these polymers act as unimolecular containers that can be loaded with up to 27 wt % hydrophobic guest molecules.
This paper reports the synthesis and characterization of a novel class of dendronized polymers which are based on styrene functionalized dendritie L-lysine macromonomers. Free radical polymerization of zeroth and first generation macromonomers afforded dendronized polymers with number-average degrees of polymerization (DP) between 50 and 240, corresponding to number-average molecular weights between 50 x 103 and 240 x 103 g/mol. In contrast, only short oligomers (DP = 5-15) were obtained on polymerization of the second generation dendritic L-lysine macromonomers. Molecularly resolved AFM images allowed first insight into the structure of these peptide dendronized polymers. Depending on the degree of polymerization, either rods, short rods, or globular structures were found.