Continuous Chromatography Device to Economically Purify Clinical-grade Antibodies

描述（申请人提供）：单克隆抗体（mab）已成为癌症治疗的主要药物类别，超过150种抗肿瘤单克隆抗体正在生物制药管道中。大多数单克隆抗体治疗必须以4-15毫克/公斤的剂量施用，导致每位患者每年的费用高达10万美元。单抗治疗的高昂价格给患者、保险公司和卫生保健系统带来了巨大的经济负担。为了使这些药物在医疗保健行业中实际应用，必须降低开发和生产这些药物的成本。临床生产费用直接影响到总体药物开发成本。蛋白质表达、细胞培养和生物反应器技术的最新发展导致了蛋白质生产和单抗滴度的实质性进步。下游净化工艺的发展没有跟上步伐，这是阻碍成本效益和稳健制造的瓶颈。目前，下游加工（DSP）占单抗生产总成本的70%。“工业标准”蛋白A捕获（PAC）是最昂贵的DSP步骤，占每克产品总成本的40%。当前的PAC方法仍然在顺序批处理过程中使用一个大列。与标准批处理方法相比，连续SMB（模拟移动床）色谱法具有显著的优势，包括更有效地使用昂贵的吸附剂和更小的色谱柱，减少缓冲消耗，以及在稳态条件下操作，允许更强大的过程分析。在一期SBIR项目（R43 CA162632-01）中，我们研究了使用我们的实验室规模Octave(tm) SMB系统开发连续PAC工艺纯化临床级单克隆抗体的可行性。当我们的连续工艺与标准批工艺直接比较时，我们获得了等效或更好的单抗纯度。然而，目前的Octave系统不是为符合cGMP或临床生产所需的规模而设计的。在II期研究中，我们建议基于Octave阀设计和I期研究结果，开发一种大规模连续色谱装置，用于临床级抗体的经济纯化。II期设备将支持高达2升/分钟的流速，并在8-20小时内处理500升含有5-10克/升单克隆抗体的培养液，这符合未来对200公斤/年治疗性单克隆抗体的需求。第二阶段的设备和优化的PAC工艺将使生产效率比批量方法提高至少3倍，并将具有一次性使用的流程，以消除对卫生和运动之间重新验证的需要。这个第二阶段的项目将开发至少一个原型设备，将被放置在一个Beta测试站点。该设备将是一个可定制的即插即用色谱模块，与未来的集成连续生物处理设施兼容。该项目符合2011年FDA战略计划，该计划寻求改进产品制造技术的发展，包括连续工艺而不是批量方法。

DESCRIPTION (provided by applicant): Monoclonal antibodies (mAbs) have become the leading drug class for cancer treatment, and over 150 anti-neoplastic mAbs are in the biopharmaceutical pipeline. Most mAb therapies must be administered in doses of 4-15 mg/kg, resulting in per patient costs of up to $100,000 per year. The high price of mAb therapy causes a significant financial burden for patients, insurance companies and the health care system. To be- come practical for the health care industry, the cost of developing and producing these drugs must be reduced. Clinical manufacturing expenses directly contribute to the overall drug development costs. Recent developments in protein expression, cell culture, and bioreactor technologies have led to substantial advancements in protein production and mAb titers. The development of downstream purification processes has not kept pace and represents a bottleneck that impedes cost-effective and robust manufacturing. Currently, downstream processing (DSP) accounts for up to 70% of the total mAb production cost. The "industry-standard" Protein A capture (PAC) is the most expensive DSP step, contributing up to 40% of the total cost per gram of product. The current PAC method still uses one large column in a sequential batch process. Continuous SMB (simulated moving bed) chromatography offers significant advantages over standard batch methods, including more efficient use of expensive adsorbent with smaller columns, reduced buffer consumption, and operation under steady-state conditions, allowing more robust process analytics. In the Phase I SBIR project (R43 CA162632-01) we investigated the feasibility of developing a continuous PAC process for the purification of clinical-grade mAbs using our lab-scale Octave(tm) SMB System. We obtained equivalent or better mAb purity when our continuous process was directly compared with the standard batch process. How- ever, the current Octave System is not designed for cGMP compliance or the scale required for clinical manufacture. In Phase II we propose to develop a large-scale continuous chromatography device for economical purification of clinical-grade antibodies, based on the Octave valve design and our Phase I findings. The Phase II device will support flow rates up to 2 L/min and processing of 500 L culture fluid containing 5-10 g/L mAb in 8-20 hours, which matches the future demand for therapeutic mAbs in the range of 200 kg/yr. The Phase II de- vice and optimized PAC process will increase productivity at least 3-fold relative to batch methods, and will feature a single-use flow path to eliminate the need for sanitation and revalidation between campaigns. This Phase II project will develop at least one prototype device that will be placed at a Beta test site. The device will be a customizable plug-and-play chromatography module compatible with future integrated continuous bioprocessing facilities. This project fits with the 2011 FDA strategic plan, which seeks development of improved product manufacturing technologies including continuous processes rather than batch approaches.