• Dr. Mohan Dewan assisted by Adv. Shubham Borkar

Accidental Inventions – Sildenafil Citrate
The little blue pill which changed the world

Accidental Inventions as the name suggests refer to the discovery or creation of something new or useful that was not intentionally sought after. Accidental inventions have played a significant role in shaping our world, from the discovery of penicillin to the creation of the microwave oven. In some cases, accidental inventions have even led to entire industries and new fields of research. These inventions often arise from unexpected or accidental circumstances, such as a laboratory mishap or a chance encounter. While not all accidental inventions may be successful or have significant impact, they serve as a reminder that innovation can come from unexpected sources and that sometimes the most ground-breaking discoveries can be the result of chance. In this Accidental Inventions series of articles we will be telling you about some of the lesser known accidental inventions.

*We do not claim any copyright in the above images. The same have been reproduced for academic and representational purposes only. The bill pill as shown above is the registered trademark of Pfizer Inc.

Development of ground-breaking medications often follows a meticulously planned research path, but every once in a while, a serendipitous discovery alters the course of medical history. Such is the case of ‘Sildenafil Citrate’, better known by its trade name, “Viagra”. Originally developed to treat cardiovascular conditions, this little blue pill has led to transform and revolutionize the lives of millions of men.

In the early 1990s, pharmaceutical company Pfizer was working hard on a drug intended to manage and treat hypertension (high blood pressure) and angina (chest pain caused by reduced blood flow to the heart). A team of researchers, led by Dr. Ian Osterloh, Peter Dunn and Albert Wood had set out to develop a drug that would dilate blood vessels and reduce blood pressure. The compound they were investigating was initially called UK-92480.

In the quest for a solution to cardiovascular problems, the researchers conducted a series of clinical trials. During the trials, an unexpected and peculiar side effect was caused to Male patients wherein they reported a surprising increase in their erections, leading researchers to re-evaluate the potential applications of their discovery.

The researchers upon observing the unintended but remarkable effect which the UK-92480 had caused in enhancing blood flow realized the vast ramifications it could have on the community as Erectile Dysfunction (ED) had long been a challenging issue for many men.

Pfizer thereafter initiated a series of clinical trials specifically designed to investigate the effects of UK-92480 on this function. The results were nothing short of astounding.

In 1990, Pfizer originally filed a Patent application no. 5,250,534, which received a 283-day patent term extension giving it an expiration date of March 29th, 2012. On 13 May 1994, by claiming priority to the UK application, (four years prior to Viagra’s launch) Pfizer filed a second PCT patent application no. 6,469,012 (international publication number WO 94/28902) titled, “Pyrazolopyrimidinones for the treatment of impotence”, in the designated thirteen countries (including, e.g., Australia, Canada, China, Japan, Korea, the United States) and EPO (the European Patent Convention then had sixteen member countries). This remained the key document for Pfizer’s patents in many countries. In addition, Pfizer also filed national patent applications in countries which were not members of the PCT in the early 1990s, including some Southern American countries. However, since Pfizer tried to pursue exclusiveness for its patent in the world, it met challenges in many countries as several of Pfizer’s applications were invalidated or rejected by reasons of obviousness or insufficient disclosure.

Viagra patent 6,469,012.
*We do not claim any copyright in the above image. The same has been reproduced for academic and representational purposes only”.

In 1998, Dr. Nicholas Terrett who is considered ‘the father of Viagra’ named the invention as we know it today, as the word Viagra expressed vim, vigor, and vitality that a man was looking to experience and achieve in overcoming erectile dysfunction. Viagra appears to be a take on the Sanskrit word “vyāghrá” (व्याघ्रः) which means Tiger.

On March 27, 1998, the US FDA approved the use of the drug Viagra, which led to Pfizer forever altering the landscape of ED treatment.  In the following weeks, more than 40,000 Viagra prescriptions were dispensed by U.S. pharmacists.

The introduction of Viagra also had a profound impact on society and culture. For many men, it offered a new lease on life, enhancing their self-esteem and quality of life. Couples around the world celebrated the newfound ability to maintain a healthy and active sexual life, and the term "erectile dysfunction" became more openly discussed and destigmatized.

Viagra soon became a symbol of vitality, and its cultural significance extended well beyond the realm of medicine. Not only did it inspired discussions about human sexuality, relationships, and aging but the "blue pill" even made its way into popular culture which included movies, and TV shows.

By 1996, Pfizer decided that China would be an important market for the drug and filed a trademark application for the English language word ‘Viagra’ with the Chinese Trade Mark Office (CTMO) on October 24, 1996. Apparently, Pfizer did not feel the need to file a Chinese transliteration of its English trademark immediately and did not file its first Chinese-language trademark application until May 1997. After its official launch in the United States in 1998, Viagra proved to be immensely popular in China as well.

However, a Chinese company, Guangzhou Viamen Pharmaceutical Company (Viamen), filed an application for the mark “Weige” (伟 哥) (meaning ‘Great Older Brother’ - a Chinese nickname for Viagra) and even got a registration for the same. Therefore, Pfizer had to adopt the trademark “Wai Aike” (万艾可),” which is a transliteration of Viagra and has no meaning in the Chinese language.

However, a Chinese company, Guangzhou Viamen Pharmaceutical Company (Viamen), filed an application for the mark “Weige” (伟 哥) (meaning ‘Great Older Brother’ - a Chinese nickname for Viagra) and even got a registration for the same. Therefore, Pfizer had to adopt the trademark “Wai Aike” (万艾可),” which is a transliteration of Viagra and has no meaning in the Chinese language.

In July 2009, Pfizer lost its final appeal on this issue in the Supreme People’s Court wherein it was ruled that Viamen was the undisputed owner of the Weige trademark in China.

Pfizer did achieve victory in a related trademark dispute in connection with Viagra in China. Stung by its lack of foresight concerning the Chinese name for Viagra, Pfizer filed a trademark application for the distinctive blue colour and three dimensional diamond shape of its pill (3D trademark) which was grnted registration on May 28, 2003, by the CTMO. Later, Pfizer sued Viamen and various other Chinese companies for infringement of its 3D trademark and sought an injunction and $6 million in damages.

In 2012, there were around 8 million Viagra prescriptions reported worldwide which amounted for gross sales of about $2 billion. Till March 2016, at least nine other companies filed applications with the US FDA to manufacture a generic version of Viagra.  However, Pfizer took aggressive steps to guard its IP and released its own generic version of Viagra, as the “little white pill” at half the price of the original Viagra pill in December 2017. Today, the brand Viagra has become a leader in its market category and linked with its intended purpose, just as brands like Kleenex and Xerox which have become synonymous with their products. The accidental discovery of sildenafil citrate, serves as a compelling reminder of the unpredictable nature of scientific breakthroughs.

It is important to understand in case of brands that are likely to draw wide interest and attention, not only should manufacturers obtain the requisite IP registrations in the English-language but also adopt a more precautionary approach and plan well in advance in considering and obtaining registrations for foreign language transliteration and variants  of their trademarks. Hence, advice from IP experts is instrumental in such scenarios, especially in an area such as Intellectual Property Rights, which is a field that is both vitally important and full of pitfalls.


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