Chemotherapy is one of the most common treatments for cancer that uses one or more anti-cancer drugs as a part of the standardized chemotherapy regimen. Cytotoxic chemicals delay and prevent cancer cells from multiplying, invading, and metastasizing. However, the significant drawbacks of cancer chemotherapy are the lack of selectivity of the cytotoxic drugs to tumour cells and normal cells and the development of resistance by cells for the particular drug or the combination of drugs. Multidrug resistance (MDR) is the low sensitivity of specific cells against drugs associated with cancer chemotherapy. The most common mechanisms of anticancer drug resistance are: (a) drug-dependent MDR (b) target-dependent MDR, and (c) drug target-independent MDR. In all the factors, the overexpression of multidrug efflux systems contributes significantly to the increased resistance in the cancer cells. Multidrug resistance due to efflux of anticancer drugs by membrane ABC transporters includes ABCB1, ABCC1, and ABCG2. ABCB1 inhibition can restore the sensitivity of the cancerous cells toward chemotherapeutic drugs. In this review, we discussed ABCB1 inhibitors under clinical studies with their mode of action, potency and selectivity. Also, we have highlighted the contribution of repurposing drugs, biologics and nano formulation strategies to combat multidrug resistance by modulating the ABCB1 activity.

化疗是最常见的癌症治疗方法之一，它使用一种或多种抗癌药物作为标准化化疗方案的一部分。细胞毒性化学物质可延缓和防止癌细胞增殖、入侵和转移。然而，癌症化学疗法的显着缺点是细胞毒性药物对肿瘤细胞和正常细胞缺乏选择性，以及细胞对特定药物或药物组合产生耐药性。多药耐药性 (MDR) 是特定细胞对与癌症化疗相关的药物的低敏感性。最常见的抗癌药物耐药机制是：(a) 药物依赖性 MDR (b) 靶点依赖性 MDR，和 (c) 药物靶点非依赖性 MDR。在所有因素中，多药外排系统的过度表达显着增加了癌细胞的耐药性。抗癌药物通过膜 ABC 转运蛋白外流引起的多药耐药性包括 ABCB1、ABCC1 和 ABCG2。ABCB1抑制可以恢复癌细胞对化疗药物的敏感性。在这篇综述中，我们讨论了临床研究中的 ABCB1 抑制剂的作用方式、效力和选择性。此外，我们还强调了重新利用药物、生物制剂和纳米制剂策略通过调节 ABCB1 活性来对抗多药耐药性的贡献。ABCB1抑制可以恢复癌细胞对化疗药物的敏感性。在这篇综述中，我们讨论了临床研究中的 ABCB1 抑制剂的作用方式、效力和选择性。此外，我们还强调了重新利用药物、生物制剂和纳米制剂策略通过调节 ABCB1 活性来对抗多药耐药性的贡献。ABCB1抑制可以恢复癌细胞对化疗药物的敏感性。在这篇综述中，我们讨论了临床研究中的 ABCB1 抑制剂的作用方式、效力和选择性。此外，我们还强调了重新利用药物、生物制剂和纳米制剂策略通过调节 ABCB1 活性来对抗多药耐药性的贡献。