Actelion’s mission to bring innovative medicines to patients is realized through global, cross-functional life cycle teams organized by development function. The life cycle of any drug involves four phases – discovery and research, development, regulatory review and approval, and commercialization/ marketing. It takes approximately 10-12 years from the initiation and identification of the drug target to bring the drug into the market.
Discovery and research
The first step in the drug discovery process is to identify a suitable target. This is a molecule or a protein receptor that is specifically associated with a disease condition or pathology. For this purpose, it is important to understand how the disease occurs at the molecular, cellular, and genetic levels. Once a target is identified, the next step involves understanding how the target plays a role in the disease process. This is followed by testing of the target against different known and new compounds to identify either one or several ‘lead compounds’ which interact with the target and show the potential to either neutralize or slow the disease process.
The drug development phase involves rigorous testing and optimization of the selected compounds to identify the ‘lead structure or candidate drug’ which might be the most effective. Testing required by the health authorities is done in cells (in vitro) and in animals (in vivo) to study metabolism (pharmacodynamics and pharmacokinetics), safety, toxicity, dosage, and efficacy. The part of the development process in which the candidate drug is thoroughly investigated, optimized, and prepared for testing in humans is referred to as the ‘preclinical phase’. During the clinical phase of development, the efficacy and safety of a drug candidate is investigated in patients.
Regulatory review and approval
Results obtained in a clinical trial establish whether there is evidence to support the safety and efficacy of the candidate drug in treating the diseased condition. At this stage, applications with all the necessary information, including quality, preclinical and clinical data collected during development of the product,are submitted to the relevant regulatory authorities in order to obtain approval to market the drug in their jurisdictions (e.g., a New Drug Application (NDA) in the US, and a Marketing Authorisation Application (MAA) in the EU). Regulatory agencies exist in most territories to oversee the development, approval, and marketing of drugs.
The last phase in the drug development process is the marketing or commercialization of the drug once it has been approved. The drug manufacturer must submit marketing authorization applications in every country or territory in which it wants to sell the drug. To continue evaluating the safety and efficacy of the marketed drug, and for further development, Phase 4 clinical trials are conducted by the manufacturer, and such post-marketing clinical studies are mandatory in some territories.