Effective Market Exclusivity of New Molecular Entities for Rare and Non-rare Diseases

Orphan Drug Label Expansions: Analysis Of Subsequent Rare And Common Indication Approvals

The Orphan Drug Act of 1983 was enacted to provide financial incentives to stimulate drug development for rare diseases. In recent years, concerns have been raised regarding these orphan drugs, including how many are being approved for both rare and common diseases and the number of subsequent indication approvals. Policy makers have suggested modifications to the Orphan Drug Act's incentives to address these concerns. In this study we investigated the approval "family trees" of orphan drugs. We found that 491 novel orphan drugs were approved between 1990 and 2022. To date, 65 percent have been approved for a single rare disease, 15 percent have been approved for multiple rare diseases, and 20 percent have been approved for both rare and common diseases. Ten percent of orphan drugs received a subsequent indication approval for a pediatric population of an orphan disease. Revenue estimates from 2021 show that one-third of the drugs approved for both rare and common indications and 6 percent of rare-only drugs were among the 200 top-selling drugs worldwide. The results have implications for the possible externalities of modifying the incentives of the Orphan Drug Act, such as a potential decrease in the initiation of programs to develop pediatric rare disease drugs.

Exploring the Potential Challenges for Developing Generic Orphan Drugs for Rare Diseases: A Survey of US and European Markets

OBJECTIVES

The US Food and Drug Administration in 1983 and the European Union's European Medicines Agency in 2000 implemented the orphan drug development program for rare diseases. The study aimed to find the potential challenges encountered by generic companies in developing generics for rare diseases.

METHODS

We performed a thematic analysis, which consists of qualitative and quantitative research. For data analysis of approved orphan drugs, we used statistical methods, and for the industrial case study, we selected 14 generic companies and conducted semistructured interviews related to 10 critical areas of drug development.

RESULTS

The orphan drug approvals were classified into 4 categories: the number of orphan approvals, pediatric claims, formulation, and therapeutic areas. We analyzed the approvals from 2001 to 2021; the Food and Drug Administration approved 815 drugs and European Medicines Agency approved 258 drugs. The pediatric orphan approvals were analyzed from 2010 to 2021; the average percentage of orphan drugs claim pediatric exclusivity during this period was found to be 31.8%. In formulation, we found the highest percentage of drugs belong to small molecules at 71%. In the therapeutic class, oncology drugs have a majority of approvals at 25%. The industrial case study responses revealed that the major challenge for drug development is the complexity of the disease at 21%, followed by the limited market at 17%.

CONCLUSIONS

There is a high need for generic orphan drugs in the developing countries. The generic companies can use the opportunities provided by health authorities for the benefit of both the company and the patient perspective.

Lifecycle management of orphan drugs approved in Japan

Background

The development of orphan drugs (ODs) is challenging from both development and business perspectives because of their small patient populations. To overcome such business challenges, lifecycle management (LCM), which maximizes profits by increasing sales and extending product lifetimes, is important to overcome the business challenges arising from their small patient populations. To clarify the activities of the LCM of ODs, we investigated additional indications that contribute to market expansion and marketing exclusivity using the patent extension and re-examination system of ODs approved in Japan between 2004 and 2019.

Results

The 203 ODs consisting of 173 active ingredients were approved in Japan between 2004 and 2019. Sixty-eight (39%) of the 173 active ingredients have additional indications, of which 57 have at least one non-OD indication. Three-fourths of the 203 ODs had patent rights, and most of them included substance or use claims. Although the re-examination period for most ODs was 10 years after the approval, most patents had a longer duration than the re-examination period.

Conclusions

Pharmaceutical companies were actively adding non-OD indications and were emphasizing the use of patent rights by registering extensions of substance or use patents for exclusive marketing periods. These results indicate that LCM through the addition of indications and registration of patent extensions is carried out as a strategy for many ODs in Japan, similar to the LCM of general non-ODs.

Analysis of Patent and Regulatory Exclusivity for Novel Agents in China and the United States: A Cohort Study of Drugs Approved Between 2018 and 2021

Patent and regulatory exclusivity shall constitute incentives for pharmaceutical companies to develop new drugs. This study aims to investigate the differences in the patent term extension (PTE) and regulatory exclusivity between China and the United States, and to evaluate their potential impact on the market exclusivity period of novel drugs. Small-molecule novel drugs with their first indication approved in China and the United States between 2018 and 2021 were evaluated regarding their PTE and regulatory exclusivity. The PTE length of the China-approved drugs was calculated by simulation, whereas that of the US-approved drugs was extracted from the United States Patent and Trademark Office. Thirty-two and 107 novel drugs approved in China and the United States, respectively, were included in the study. The PTE length of the US-approved drugs calculated by the China-PTE method was significantly longer than that calculated by the US-PTE method. Patent extensions should be granted for 91% of new drugs in China and 82% in the United States. The simulated median PTE length of novel drugs approved in China was significantly higher than that of the United States (5.0 vs. 2.9 years, P < 0.05). It can be expected that the implementation of the PTE policy in China would significantly extend the period of market exclusivity for novel drugs similar to that of the United States. China should fully evaluate the potential impact of the PTE policy on the market exclusivity of novel drugs and provide better incentives to the development of novel drugs in addressing unmet clinical needs when developing its regulatory exclusivity policy.

Using four decades of FDA orphan drug designations to describe trends in rare disease drug development: substantial growth seen in development of drugs for rare oncologic, neurologic, and pediatric-onset diseases

BACKGROUND

Orphan drug designations are a useful proxy to investigate trends in rare disease drug development. Drug developers must receive a designation before they are eligible for the economic incentives of the Orphan Drug Act in the United States. We created a database of all orphan drugs designated between 1983 and 2019 that included numerous drug characteristics, including therapeutic area. In addition, we constructed a "broad disease" categorization of designations as an alternative to therapeutic area, based on disease etiology and age of onset rather than organ system. By looking at the pattern of orphan drug designations over the past four decades, this analysis studied the impact of the evolving rare disease drug development landscape and considers the future of rare disease therapies over the coming decades.

RESULTS

Between 1983 and 2019, a total of 5099 drugs and biologics received orphan drug designation. Designations more than doubled between the 1980s and 1990s, almost doubled between the 1990s and 2000s, and almost tripled in number between the 2000s and 2010s. The top three therapeutic areas represented in the orphan drug designations were: oncology (1910, 37%), neurology (674, 13%), and infectious diseases (436, 9%). The broad disease categorization found that the proportion of designations for pediatric-onset diseases has increased in the most recent decade to 27%.

CONCLUSIONS

Analysis of the last four decades of orphan drug designation indicates seismic shifts have occurred in the rare disease drug development space. The number of designations granted more than quadrupled between the 1990s and 2010s. While these substantial increases led to growth in the absolute number of designations within all therapeutic areas (bar one) and broad disease categories, the relative proportions have seen considerable change over time. In the most recent decade, there have been notable increases in the proportion of drugs in oncology, pediatric-onset diseases, and neurologic disorders. The dramatic rise in overall orphan designations over the past four decades suggests we may continue to see an upward trajectory in designations leading to an increased number of approvals for drugs and biologics designed specifically for diagnosing, preventing, and treating rare diseases in the coming decades.

Orphan Designation and Cisplatin/Hyaluronan Complex in an Intracavitary Film for Malignant Mesothelioma

Pleural mesothelioma is a lung diffuse tumor, whose complete resection is unlikely. Consequently, metastases reappear where the primary tumor was removed. This paper illustrates the orphan medicine designation procedure of an intracavitary cisplatin film and related pharmaceutical development aspects requested by the European Medicines Agency (EMA) in its Scientific Advice. Since cisplatin pharmacokinetics from the implanted film in sheep resulted substantially modified compared to intravenous administration, the formation of a cisplatin/hyaluronan complex had been hypothesized. Here, the interaction between sodium hyaluronate (NaHA) and cisplatin (CisPt) was demonstrated. Size exclusion chromatography qualitatively evidenced the complex in the film-forming mixture, only showing the NaHA peak. Atomic absorption spectroscopy of the corresponding fraction revealed platinum, confirming the interaction. Reverse phase HPLC quantified about 5% free cisplatin in the film-forming mixture, indirectly meaning that 95% was complexed. Finally, a study of CisPt release from the film assessed how CisPt/NaHA complex affected drug availability. In water, a medium without chloride ions, there was no release and the film remained intact for 48 h and longer, whereas the placebo film dissolved in 15 min. In 0.9% NaCl medium, the film became more soluble, dissolving within 3–4 h. However, cisplatin release was still controlled by the existing complex in solution until chloride ions displaced it. While the film modified its dissolution with aging, CisPt release remained unaffected (90% released in 48 h).