Development of a Companion Diagnostic Assay for Detection of ADAM8-Positive Cancers

乳腺癌（BrCa）每年导致全球约685，000名女性死亡（WHO）。而激素患者 受体（HR）和人表皮生长因子受体-2（HER 2）驱动的癌症（HR+和/或HER 2+） 虽然这些患者已经受益于内分泌和HER 2靶向治疗，但他们仍然占大多数死亡。的 HR和HER 2阴性（HR-/HER 2-）亚型，也称为三阴性乳腺癌（TNBC），是最常见的乳腺癌。 侵袭性和更具挑战性的治疗，导致约25%的死亡，尽管发病率低得多。 迫切需要更有效的治疗方法。我们将细胞表面蛋白ADAM 8鉴定为独立的 BrCa患者预后不良的标志物和肿瘤生长和扩散的驱动因素。使用ADAM 8阳性（ADAM 8+） 在TNBC小鼠模型中，我们显示基于抗体（Ab）的靶向ADAM 8是一种有效的治疗（Tx）。 战略[1]。原发性TNBC的初步免疫组织化学（IHC）显示只有一个子集是ADAM 8 + (17/50或34%），这表明需要进行诊断（Dx），以确定可以从靶向治疗中获益的患者 疗法我们推出Adecto Pharmaceuticals来开发Dx和Tx产品，以改善 ADAM 8+癌症患者。ADP 2是我们的顶级Tx Ab，可减少预先存在的TNBC生长和扩散， 存活率，并增强对标准治疗化疗的反应。ADP 2被成功地人源化， 在IND使能研究之前选定的主要候选人（AD 100）。AD 100方案可以显著改善 BrCa治疗。在这里，我们建议开发一种基于IHC的Dx，用于ADAM 8+癌症，作为AD 100的伴侣。 或用于鉴定处于进行性疾病的高风险的患者的独立预后。目前尚无 Dx用于检测这些肿瘤。使用一组高度特异性的抗ADAM 8单克隆抗体（mAb）和 第1阶段SBIR资金，我们（i）优化了IHC条件，并确定ADP 2为主要Dx Ab;（ii）开发了乳腺癌 用表达低、中或高ADAM 8的3个细胞系对对照细胞系微阵列（CCM）进行染色/评分，以及 分析了患者来源的异种移植物样品;（iii）验证了IHC测定和CCM，并建立了ADAM 8 评分系统，在主要BrCa样本（完成了所有拟议的目标）。与先前的发现一致， ADP 2 IHC显示36.1%的TNBC（22/61）为ADAM 8+，非TNBC BrCas为32.8%， (115/351）。一项对HR+/HER 2-亚型进行的10年年龄调整分析，样本量最大，显示 ADAM 8评分与不良生存率相关，为该检测的预后应用提供了早期支持。在这 针对2期应用，我们提出：1）完善ADP 2测定，以允许准确表征 ASCO/CAP指南内任何BrCa样本中的ADAM 8; 2）验证ADAM 8阳性率并研究 3）使用TNBC测试测定法对AD 100应答的预测值 和HR+/HER 2-小鼠模型; 4）由临床Dx承包商完成检测试剂盒的CLIA验证。成功 完成拟议目标将导致ADAM 8 IHC检测与CLIA标准操作方案 准备在未来的临床试验中进行测试。

Breast cancer (BrCa) leads to ~685,000 deaths in women yearly worldwide (WHO). While patients with Hormone Receptor (HR) and Human Epidermal Growth Factor Receptor-2 (HER2)-driven cancers (HR+ and/or HER2+) have benefited from endocrine and HER2-targeted therapies, they still account for the majority of deaths. The HR and HER2 negative (HR-/HER2-) subtype, also known as Triple-negative breast cancer (TNBC), is the most aggressive and even more challenging to treat, leading to ~25% of deaths, despite a much lower incidence. More effective therapies are urgently needed. We identified the cell surface protein ADAM8 as an independent marker of poor BrCa patient outcome and a driver of tumor growth and spread. Using ADAM8-positive (ADAM8+) TNBC mouse models, we showed antibody (Ab)-based targeting of ADAM8 is an effective therapeutic (Tx) strategy [1]. Preliminary immunohistochemistry (IHC) of primary TNBCs revealed only a subset are ADAM8+ (17/50 or 34%), suggesting a diagnostic (Dx) will be needed to identify patients who can benefit from targeted therapy. We launched Adecto Pharmaceuticals to develop Dx and Tx products to improve the outcome of patients with ADAM8+ cancers. ADP2, our top Tx Ab, reduces pre-existing TNBC growth and spread, improves survival, and enhances response to standard-of-care chemotherapy. ADP2 was successfully humanized, and a lead candidate (AD100) selected ahead of IND-enabling studies. AD100 regimens could dramatically improve BrCa treatment. Here, we propose to develop an IHC-based Dx for ADAM8+ cancers as a companion to AD100 or a standalone prognostic for identification of patients at high risk of progressive disease. Currently, there is no Dx for detection of these tumors. Using a panel of highly specific anti-ADAM8 monoclonal Abs (mAbs) and Phase 1 SBIR funds, we (i) optimized IHC conditions and identified ADP2 as lead Dx Ab; (ii) developed a breast staining/scoring control cell line microarray (CCM) with 3 lines expressing low, medium or high ADAM8, and analyzed patient-derived xenograft samples; (iii) validated IHC assay and CCM, and established an ADAM8 scoring system, in primary BrCa samples (which completed all proposed aims). Consistent with earlier findings, ADP2 IHC showed 36.1% of TNBCs (22/61) were ADAM8+, and unexpectedly 32.8% of non-TNBC BrCas (115/351). A 10-year age-adjusted analysis of the HR+/HER2- subtype, with largest sample size, revealed ADAM8 score associated with poor survival, providing early support for a prognostic use of this assay. In this Direct to Phase 2 application, we propose to: 1) refine the ADP2 assay to permit accurate characterization of ADAM8 in any BrCa sample within ASCO/CAP guidelines; 2) verify ADAM8 positivity rates and study the prognostic value of the assay in BrCa; 3) test the predictive value of the assay for AD100 response using TNBC and HR+/HER2- mouse models; 4) complete CLIA validation of the assay by a clinical Dx contractor. Successful completion of the proposed aims will result in an ADAM8 IHC assay with CLIA standard operating protocols ready for testing in future clinical trials.