لخّصلي

Over the past decade, the attrition rate of clinical trials in drug discovery reached 90%.Although these approaches can rapidly filter out drug-like compounds, simple boundaries for individual physicochemical properties are too strict.Since then, a variety of relevant drug-likeness rules based on simple molecular properties have been developed, such as those proposed by Ghose et al. [9], Oprea et al. [10], Veber et al. [11], and Muegge et al. [12].Pharmaceutical companies spend millions of dollars to advance a new drug through clinical trials and, thus, failure in the later stages of drug development typically result in significant economic losses [3].Therefore, selecting appropriate candidates with a good balance of potency along with absorption, distribution, metabolism, excretion, and toxicity (ADMET) is an urgent scientific need.Undesirable PK properties and unacceptable toxicity are the main causes of the failure of drug candidates at the clinical trial stage [4].These rules suggest that compounds that fall within a particular range are 'drug-like'.

Over the past decade, the attrition rate of clinical trials in drug discovery reached 90%. The average number of small molecules approved by the US Food and Drug Administration (FDA) over a 5-year period was 26.8. In 2016, the approval rate of small-molecule drugs was the lowest of the past five decades, and only 12 novel small-molecule drugs were approved by the FDA 1, 2. Pharmaceutical companies spend millions of dollars to advance a new drug through clinical trials and, thus, failure in the later stages of drug development typically result in significant economic losses [3]. Undesirable PK properties and unacceptable toxicity are the main causes of the failure of drug candidates at the clinical trial stage [4]. Therefore, selecting appropriate candidates with a good balance of potency along with absorption, distribution, metabolism, excretion, and toxicity (ADMET) is an urgent scientific need.

The concept of drug-likeness was proposed to provide useful guidelines during the early stages of drug discovery to improve the chance of a chemical entering and passing clinical trials [5]. It can be defined as the sum of the molecular physicochemical properties that are characteristic of chemicals known as drugs. Indeed, drug-likeness is often used to describe PK and safety, and can also be understood as compounds with desirable ADMET properties 6, 7. Lipinski’s Rule of Five (Ro5), the original and well-known assessment of compounds with good oral absorption, was first proposed in 1997 [8]. Since then, a variety of relevant drug-likeness rules based on simple molecular properties have been developed, such as those proposed by Ghose et al. [9], Oprea et al. [10], Veber et al. [11], and Muegge et al. [12]. These rules suggest that compounds that fall within a particular range are ‘drug-like’. Although these approaches can rapidly filter out drug-like compounds, simple boundaries for individual physicochemical properties are too strict. Hence, a possibly successful drug might be missed if only one or two properties fall outside the criteria boundaries [13