1.  Introduction
The ongoing COVID-19 pandemic has imposed a heavy toll on human life, health care, global economy and almost every aspect of human life [1,2]. Yet despite its devastating effects, it has also mobilized and united many elements of the drug discovery and development process to seek therapies to address this most pressing public health emergency. In a record time frame, 36 vaccines have entered in clinical trials and 89 are in preclinical phase [3]. While it usually takes 10–15 years to develop a vaccine, in less than a year, promising results from phase III clinical trials of the Pfizer/BioNTech vaccine were recently announced with results from trials by other pharma companies expected to follow soon (Figure 1) [4].
Figure 1. Comparison between the traditional vaccine development timeline and the accelerated development time line in response to the COVID-19 pandemic
This momentous foot is a testament to the collective human resolve and can only be achieved in the presence of a global will, collaboration, and available resources needed to tackle a global health crisis of this scale. Yet as the world remains focused on COVID-19 pandemic, the humankind still faces several intricate diseases many of which do not obey the standard Mendelian rules of inheritance such as infectious diseases [5], cancer [6], rare diseases [7], and dementia [8]. Despite skyrocketing technological advances, the impression has gained ground that we are clueless about most of the diseases’ etiologies, progression and molecular mechanisms. Solving unmet medical needs is still a distant dream and there is a pressing need to develop new and effective medicines for several existing diseases. To successfully address these challenges, developing efficient strategies, novel technologies, and policies are paramount. The mounting cost, risk, and timely process are significant obstacles that hinders the drug discovery and development processes. As global momentum continues to materialize in an effort to address the ongoing pandemic, valuable lessons and perhaps plunders can be learned and applied to address other global health-related challenges humankind faces. In the following sections, major perplexing challenges to the health of humankind, the hurdles facing drug discovery and development and frontiers for potential solutions, are addressed.