Continuing Education Activity
The development of new medications in the US is a lengthy process governed by the FDA. The drug development process involves coordination between drug sponsors, clinical researchers, and regulatory authorities. All drugs must move through the pipeline of discovery, investigation, clinical trials, and FDA approval before being marketed to consumers. This activity reviews the federal regulations of medication development and highlights the interplay between the FDA, drug manufacturers, and clinical researchers.
Objectives:
- Outline specific laws about regulations of drug development by the FDA.
- Describe the New Drug Application process, including expedited review programs.
- Summarize the intellectual property laws regulating drug development.
- Explain the process of regulating the production of generic small-molecule drugs and biologics.
Introduction
Before 1906, there were few controls on drug distribution, and products were often inconsistent in strength or poorly labeled.[1] The Federal Drug Administration(FDA) was formed by the enactment of the Pure Food and Drug Act of 1906, which prohibited misleading drug labeling and created consumer protections for drug safety. The Federal Food, Drug, and Cosmetic Act (FDCA) of 1938 would replace the former act and strengthen the ability of the FDA to regulate the process of medication development. It required manufacturers to provide proof of safety and adequate information on labels.[2]
Numerous amendments were added to the FDCA to modify the regulations and oversight of the FDA. The Durham-Humphrey Amendment was enacted to regulate unsafe medications to be taken without medical supervision, distinguishing between over-the-counter and prescription drugs.[3]
In 1961, thalidomide was shown to cause severe congenital disabilities after being marketed in Europe, prompting increased regulations on medication development.[4] There were also cases of thalidomide-induced congenital disabilities in the US; however, the FDA had not approved medicine. The passage of the Kefauver-Harris Amendment in 1962 would allow the FDA to require proof that drugs were both safe and effective before approval. This amendment contained provisions for obtaining informed consent for clinical trials and initiated Good Manufacturing Practices(GMP).
Function
The FDA approval process requires comprehensive pre-clinical testing followed by multi-phase clinical trials to ensure safety and efficacy. Discovery is the beginning phase of medication development involving disease study, molecular models, and high-throughput screening to determine potential new drug molecules. Pre-clinical testing involves in-vitro and in-vivo experiments using cellular and animal models.
The submission of an Investigational New Drug (IND) application is required before being administered to human participants.[5] Once submitted, the FDA has 30 days to decide if the drug is suitable for human testing. When the FDA approves an IND, human testing can proceed with multi-phase clinical trials, which may last an average of 6-7 years and averages $48 million per drug.[6] Fewer than 14% of drug candidates will reach FDA approval during this rigorous process.[7] Additionally, serious and fatal adverse events must be reported to the FDA Adverse Event Reporting System (FAERS) within 15 days. The FDA has the power to halt clinical trials at any time if an investigational drug causes significant harm to patients. The phases of clinical trials (I-IV) are summarized in Table I.[8]
Phase I |
Initial testing of fewer than one hundred healthy patients to determine pharmacokinetics, toxicology, and drug safety in humans. Roughly two-thirds of drugs complete phase I testing and move on to phase II clinical trials.
|
Phase II |
Comprises of testing dozens to hundreds of patients with the targeted disease to determine drug efficacy and adverse effects. Only about one-third of these drugs move on to phase III. |
Phase III |
Hundreds to thousands of patients with the targeted disease are tested for drug efficacy and adverse effects. Typically, phase III trials compare treatment using the study drug against a placebo. About half of these drugs will move onto the NDA process. |
Phase IV |
Phase IV is considered post-market surveillance of the approved drug on thousands of diseased patients. Annual reports are submitted to the FDA to determine if the drug should still be available on the market.
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If drug sponsors can demonstrate adequate safety and efficacy during clinical trials phases I-III, they may subsequently submit a New Drug Application (NDA) or Biologics License Application (BLA).[9] If the FDA accepts the quality of clinical trial data, then the NDA or BLA will be approved, and drug manufacturers can begin marketing. The lengthy developmental process may be shortened with one of multiple FDA expedited review programs. These expedited processes are granted for investigational drugs that fill an unmet medical need or represent a substantial increase in efficacy for serious medical conditions.[10]
Priority review can be used for an NDA or BLA to decrease the FDA review period and may be combined with other expedited review programs.[11] Fast track review can be requested for IND applications for drugs that fulfill an unmet medical need. Fast track review allows drug sponsors to meet with the FDA to advance drug development. Breakthrough therapy review can be requested for drugs with clinical data demonstrating significant improvement over existing drugs. Breakthrough drugs also allow drug sponsors to meet with the FDA and sometimes allow sponsors to avoid components of the standard review process. Accelerated approval is intended for developing drugs with long-term clinical endpoints that may be difficult to measure during clinical trials. Other expedited review programs may also be used alongside accelerated approval.
The FDA continues to monitor newly approved drugs and biologics for long-term safety. Phase IV clinical trials are used for post-market surveillance, which involves thousands of participants.[8] During phase IV, drug sponsors must send periodic reports on safety and tolerability to the FAERS. Additionally, the FDA regulates the use of potentially harmful drugs by requiring manufacturers to use Risk Evaluation and Mitigation Strategy(REMS) programs. Such programs were formalized by the Food and Drug Administration Amendments Act of 2007 and help to ensure safe drug use by consumers.[12] For example, isotretinoin is commonly used for acne treatment but has teratogenic effects if taken while pregnant. Isotretinoin is dispensed by a REMS program called iPLEDGE. The iPLEDGE program mandates that female patients using isotretinoin must use two birth control methods, take doctor-administered pregnancy tests, and complete online educational modules to mitigate the risk of bearing children with severe congenital disabilities.[13] There are currently 61 REMS programs with varying degrees of implementation and effectiveness.[14]
US governing authorities heavily regulate intellectual property. Drug patents are granted by the US Patent and Trademark Office, whereas data exclusivity for new medicines is set by the FDA. Exclusivity involves inhibiting the approval of competing drugs for a set period to balance novel drug creation and consumer medication accessibility. The FDA allows 5 years of exclusivity for novel small-molecule drugs and 12 years for biologics.[15] New clinical uses of existing drugs may be granted 3 years of exclusivity. Under the Best Pharmaceuticals for Children Act, an additional 6 months of exclusivity may be added to existing pediatric drugs. Under the Orphan Drug Act, 7 years of market exclusivity is granted for the treatment of rare diseases.[16]
Following the expiration of patents for name-brand drugs, the FDA regulates the production of generic drugs by requiring the submission of an Abbreviated New Drug Application(ANDA). The FDA approval of an ANDA requires evidence from a manufacturer that their production of a generic small-molecule drug is bioequivalent to the existing name-brand drug.[17] Generic drug applications are considered abbreviated because the FDA does not require pre-clinical and clinical trials to be performed. Exclusivity for ANDAs may be granted for 180 days during a patent challenge by a generic drug manufacturer, as well as 180 days for competitive generic therapy.
However, biologics are regulated under a different set of rules and require submission of an abbreviated Biologics License Application(aBLA). Generic biologics, or biosimilars, may differ considerably in molecular structure from the original biologic, unlike generic small-molecule drugs.[18] Manufacturers must prove that a biosimilar exhibits equivalent safety and efficacy as the name-brand biologic despite having molecular heterogeneity. All manufacturers must adhere to GMP regulations set in place by the FDA to ensure quality and safety during medication production.
Issues of Concern
Due to the stringent requirements set by the FDA, some studies have revealed the issue of “drug lag” in the US markets. Particularly in the 1970s, new drugs were often approved and marketed far earlier in European markets than in US markets.[19] This resulted from increased regulatory standards in the US, which increased the length of time required to verify drug safety. Therefore, while European consumers were already using novel medications, US consumers often could not access these drugs. The duration of clinical trials continues to increase across all phases as the scope of federal regulations continues to expand, which may continue to hinder the ability of the FDA to approve medications promptly. However, there is some evidence to suggest that the burden of drug lag has decreased in recent years as federal regulations on the pharmaceutical industry have evolved.[20]
The increasing cost of performing clinical trials creates another significant barrier to the approval of new drugs. The average cost of performing a clinical trial is nearly $48 million per drug.[6] One reason for the rising costs of clinical trials includes increasing clinical procedures and administrative staff needed throughout each trial.[21] Greater disease complexity, increasing comparator drugs, and higher failure risk contribute to the growing costs of clinical trials. The rising costs may adversely affect drug manufacturers, leading to fewer new drugs for consumers and decreased pharmaceutical innovation.
Clinical Significance
The regulations provided by the FDA have assured the production of safe and efficacious medications for consumers. For instance, the Kefauver-Harris Amendment, also known as the "Drug Efficacy Amendment," required pharmaceutical companies to show evidence of drug efficacy before approval. The legislation also worked to prevent the rebranding of generic drugs as breakthrough drugs at a higher price. As a result of modern drug regulations, physicians and pharmacists can inform patients about adverse effects, safe dosages, and the proven effectiveness of medicines in treating disease. In addition, drug sponsors must monitor adverse drug reactions through the FAERS to safeguard clinical trial participants and consumers. Historically, the FDA has stopped drug trials prematurely due to high rates of adverse events in concordance with such reporting systems. Thus, patient safety is the foundation of many laws governing drug development.
Government oversight of intellectual property laws also has clinical implications. Drug manufacturers are allowed drug data exclusivity for several years, during which the manufacturer can recoup the huge costs associated with research and clinical trials. Data exclusivity promotes pharmaceutical innovation so that novel drugs are created for consumers. Privatized drug innovation is balanced by allowing cheaper generic drugs to be produced after data exclusivity ends. Clinicians are therefore able to prescribe more affordable generic drugs to their patients without compromising on drug efficacy. The regulations for generic drugs provide significantly better health care to consumers from a lower socioeconomic background.
Enhancing Healthcare Team Outcomes
Federal regulations have evolved over time to improve consumer safety. As mentioned, the FDA makes attempts to balance pharmaceutical drug innovation with public access to affordable medicines. The processes involved have implications on physicians and pharmacists prescribing medications. Physicians and pharmacists need to consider the bioequivalence of generic drugs when prescribing and educating patients. Furthermore, health professionals involved in researching novel drugs should be cognizant of the processes and federal regulations surrounding drug development. A better understanding of these regulations by physicians and pharmacists alike will enhance the difficult process of drug development. [Level 5]