Patents and Access to Medicines in Thailand ?The ddl case and beyond*

Jakkrit Kuanpoth **

I. INTRODUCTION

In 2003, it was estimated that, globally, 30 million people have died since the beginning of the HIV/AIDS epidemic, while 40 million people were living with HIV/AIDS. Among them, 6 million people in developing countries are in need of treatment with anti-retroviral medicines. Yet only 300,000 of them have access to such medicines.

Thailand is currently one of the countries that are facing an AIDS crisis. It is estimated that around one million adults and children are living with HIV/AIDS. While the number of new anti-retroviral drugs entering the market continues to grow, only about five percent of the affected population in Thailand has access to them. The main reason for the inaccessibility of anti-retroviral drugs in Thailand is the high cost of treatment. Treatment with anti-retroviral drugs is currently not covered by the national health insurance. Thus, HIV/AIDS treatment in Thailand depends upon the consumers' ability to pay, and only one percent of HIV/AIDS
patients can afford to purchase anti-retrovirals for themselves. As the number of those infected and affected by HIV/AIDS continues to increase, individuals, families and the society face an increasing economic and social pressure to provide appropriate health care, psychosocial support and medical treatment that would prolong the lives of those infected.

For these reasons, the initiative of an NGO and two Aids patients to, first, have the Thai government grant a compulsory licence over one of the AIDS medicaments, the ddI drug, and, second, request (partial) revocation of the corresponding patent has evoked interest far beyond Thailand. Due to the peculiarities of Thai patent law, the request for a compulsory licence looked more promising, but ultimately failed, while the request for invalidation, assisted by a public campaign, was successful. The case has revealed serious defects of the Thai patent system that highlight the difficulties for developing countries to properly use and apply the patent system as a motor of domestic innovation.

II. Facts of the ddl Cases
Didanosine (ddI) is one of the anti-retroviral drugs that the World Health Organisation (WHO) recommends for HIV/AIDS treatment. The drug when used with zidovudine and lamivudine, has proved an effective reverse transcriptase inhibitor against the disease, especially for patients intolerant to zidovudine, or in whom zidovudine has failed.¹

The ddI drug was developed in the U.S. by two scientists working for the National Institute of Health (NIH), a U.S. public research institution. In 1989, two patents (U.S. 4861759 and U.S. 5616566) over ddI were issued by the USPTO to the Department of Health and Human Services. The patents were subsequently licensed to Bristol-Myers Squibb (BMS), a company incorporated in Delaware, in order to produce and market the product world-wide under the trade mark ?Videx?. The licensing agreement, under which BMS agrees to pay royalties of 5 percent of sales, contains a fair pricing clause and requires commercialisation of ddI for the public benefit.²

Having secured marketing rights over ddI, BMS improved the drug based on NIH?s formulation as a single tablet containing ddI and an appropriate amount of antacid. In 1991, the company filed a patent application for the improved formulation of ddI, yet the application was rejected by the USPTO on grounds of obviousness. BMS re-submitted a second application with the USPTO in 1997, initially with the same result.. The rejection was based on the fact that the method of combining ddI with the appropriate amount of antacid was well known to the person ordinarily skilled in the art. The company responded by arguing that non-obviousness was based on the new buffer system that helped to reduce the antacid component. The claims were finally accepted by the examiner after BMS had agreed to limit the composition to specific ingredients and proportions.

BMS filed a corresponding patent application with the Department of Intellectual Property (DIP) of Thailand on 7 July 1992 for ?improved oral dosing formulations of dideoxy purine nucleosides?. It was claimed in the application that invention related to pharmaceutical components providing improved oral dosing formulations of ddI. The claims were directed to the method of adding a buffer (antacid) that provided the following advantages for the treatment of HIV/AIDS:

(i) improve pharmaceutical formulations for nucleosides which are not stable in acid in order to reduce the amount of ddI and facilitate oral dosage,
(ii) reduce acid in the stomach, thereby minimising the side effect of diarrhoea and/or the imbalance of pH and electrolytes, and
(iii) improve the taste. The claims in the application filed in Thailand were identical to those contained in the second US application. BMS could not file a patent over the original version of ddI due to lack of novelty. And as the Thai Patent Act was amended only in 1992 to allow for the patenting of pharmaceutical substances, neither could the NIH. Thus, BMS could only claim an improved
dosage formulation of ddI, not ddI as such.

Although Thai patent law requires applications to be substantively examined, the DIP due to limited resources and facilities hardly conducts a patent search and examination, but simply grants patents pursuant to the examination results of foreign offices, particularly those of developed countries that are considered more capable of thoroughly examining applications.

The patent application that was filed in Thailand claimed a drug dosage between 5-100 mg of ddI per dose. In 1997, after the application was published, BMS requested the DIP to amend its application and remove the limitation on the dosage range mentioned in the claims. Under Sec. 20 Patent Act B.E. 2522, an amendment to a patent application can be made only when it does not incorporate additional subject matter into the essential elements of the invention. The Ministerial Regulation No.21 B.E. 2542, Clause 16, which implements Sec. 20, requires that an application for the amendment must be made before the publication of the application unless so authorised by the DIP?s Director-General.³ The DIP approved the request for amendment, and in January 1998, a patent covering all dosage forms of ddI was granted to the company. The amendment made the patent application in Thailand equivalent to the first US application for the ddI formulation that had been rejected by the USPTO.

III. The Request for a Compulsory Licence
Soon after the patent was granted, in 1999, a campaign against the ddI patent was launched by the AIDS Access Foundation and the Network of People Living with HIV. BMS was accused of charging exorbitant prices for ddI,⁴ and DIP of issuing a patent over the ddI formulation. The Thai government was urged to issue a compulsory license under Sections 51 and 52 of the Patent Act B.E. 2522 and to allow the Government Pharmaceutical Organisation (GPO) to manufacture the drug. However, the government refused to invoke the compulsory licensing scheme, fearing negative trade repercussions from Thailand?s trading partners. Instead, it asked the GPO to produce ddI in powder form, which was not covered by BMS? patent. That was fine as far as it went, yet the powdered form of ddI had several disadvantages, e.g. more side effects and more difficulty to consume.

Footnotes

* The article was published in Intellectual Property Quarterly, No.2, 2006, pp.149-159.
** LL.B. (Hons.), Barrister-at-Law (Thai Bar), LL.M. (Warwick), Ph.D (Aberdeen); Senior Lecturer, Faculty of Law, University of Wollongong, Australia.
1. In order to be effective over time and to reduce the likelihood of resistance, the WHO recommends that anti-retroviral treatments be taken in certain combinations. The standard treatment recommended by the WHO is a ?triple cocktail? therapy that includes at least one protease inhibitor and two other drugs.
2. At least in this case, the high price of the pharmaceutical was not the result of high research costs. In fact, many essential drugs, like ddI, were developed within publicly funded research. Often, private companies have entered into licencing agreements with public research institutes in order to get the medicines to market.
3. Sec. 20 Patent Act B.E. 2522 as amended in 1999,; Ministerial Regulation No. 21 B.E.2542, Clause 16.