The recently signed Trans-Pacific Partnership (TPP) will "dramatically" restrict access to affordable medicine in every country that ratifies it, according to a US law expert.

Writing in scientific journal PLOS Medicine, Professor Brook Baker of the Northeastern University School of Law in Boston argues the TPP will:

The TPP was signed at SkyCity in Auckland just over a month ago. Prime Minister John Key last year admitted New Zealand's drug-buying agency Pharmac may face some higher costs, but said they wouldn't be passed onto the public - promising prescriptions would stay at $5.

"If patents were to run a little bit longer, in theory the Government could pay a little bit more," he said in June. "But on the other side of it, if by signing the agreement we get a huge amount of revenue through increased economic activity, it's all balanced."

It could take up to a couple of years for each of the 12 signatories to ratify the TPP. Prof Baker says this time "must" be used to convince lawmakers to reject it.

"Buried in 6,000-plus pages of text, annexes, and side letters, there are multiple provisions -- complex in their articulation, but simple in their effect: they dramatically increase monopoly protections for the transnational originator pharmaceutical industry," he writes.

By weakening standards on what can and can't be patented, Prof Baker says pharmaceutical companies are encouraged to seek "secondary" patents on existing medicines for "minor variations of an active ingredient, new formulations and dosages, new uses or methods of use, and new processes of synthesis and manufacture… even though research and development costs are significantly lower for a medicine already known to be safe".

The TPP also states if there is an "unreasonable delay" in granting a patent -- within five years of application, or three years of a request for examination -- the length of the patent must be extended to compensate. Prof Baker cites a US study showing this would add an average of 3.6 years to the length of a patent.

He also claims the introduction of generic medicines based on expired patents is also under threat. Intellectual property (IP) is defined as an investment in the TPP, and therefore subject to its investor-state dispute settlement clauses.

He cites a US$500 million claim brought against Canada by a pharmaceutical company after the government there revoked patents on two medicines the courts ruled didn't meet the standards of patentability.

"Canada will have to spend millions of dollars to defend against this claim even if it ultimately wins, which is likely," writes Prof Baker.

"The even greater danger is that other, poorer countries will be intimidated away from regulating or otherwise acting against the interests of foreign IP investors, even if they are doing so in a non-discriminatory fashion and in the interests of public health."

That claim was brought under the North American Free Trade Agreement (NAFTA).

"TPP member states can expect an avalanche of IP-related claims from disappointed pharmaceutical companies that think their legitimate expectations of future profits have been thwarted."

Instead of helping Big Pharma, Prof Baker says the TPP provisions affecting access to healthcare should be scaled back to guidelines and standards agreed at the World Trade Organization in 1994.

"Health advocates should convince the US Congress and opponents in other countries to reject an agreement that could so adversely impact access to medicines."

According to his profile on the Northeastern University website, Prof Baker specialises in intellectual property rights, trade, access to medicines, and medicines' regulatory policy. He has worked with international groups, including the World Health Organization, African Union, ASEAN and the Millenium Development Goals Project, on increasing access to healthcare, particularly in regards to HIV/AIDS.

The TPP grew out of trade negotiations spearheaded by New Zealand under Helen Clark's leadership. Though signed by all 12 countries, it still faces an uphill battle -- Labour has promised to fight certain aspects of it "tooth and nail", and it is opposed by US presidential candidates Donald Trump and Bernie Sanders.

The Government's TPP roadshow, designed to sell the deal to the public, opened to protests earlier this week.

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