The cellular membrane hinders the effective delivery of therapeutics to targeted sites. Cellpenetrating peptide (CPP) is one of the best options for rapidly internalizing across the cellular membrane. CPPs have recently attracted lots of attention because of their excellent transduction efficiency
and low cytotoxicity. The CPP-cargo complex is an effective and efficient method of delivering several
chemotherapeutic agents used to treat various diseases. Additionally, CPP has become another strategy
to overcome some of the current therapeutic agents' limitations. However, no CPP complex is approved
by the US FDA because of its limitations and issues. In this review, we mainly discuss the cellpenetrating peptide as the delivery vehicle, the cellular uptake mechanism of CPPs, their design, and
some strategies to synthesize the CPP complex via some linkers such as disulfide bond, oxime, etc. Here,
we also discuss the recent status of CPPs in the market.