OPINION: We are senior medical specialists deeply concerned about the Trans-Pacific Partnership (TPP). Nobel Laureate economists and broad groups of national and international health and legal experts, climate scientists, international human rights experts, and civil society are also concerned.

Unfortunately, in a recent speech, Trade Minister Tim Grosser labelled us all "politically irrelevant" and said our views were driven by ideology and not based on evidence.

He closed the door on any consultation on or discussion of problems that may result from the TPP.

The ambition of the TPP to reset global investment rules is without precedent. It includes legal rules covering issues such as investor protections and intellectual property rights.

These rules allow for extension to monopolies, and for corporadhtions to sue governments if they introduce policies that interfere with potential corporate profits.

Even the most optimistic supporters have to concede that these rules may not only prove very costly but will also reshape our democracy. We believe that this is politically relevant.

The negotiations are completely concealed from the New Zealand public. Yet they are available to more than 600 United States corporations which appear to influence the negotiating process.

The negotiating documents will remain confidential for four years after negotiations are concluded or abandoned.

New Zealanders may therefore be subject and bound to a secret agreement, which is virtually impossible to reverse.

It is naive to dismiss the obvious conflict of interest in the process and to expect that these corporations will not set terms that further their interests ahead of those of the New Zealand people who are not even allowed to know what is traded away. We believe that this is politically relevant.

We have decades of experience delivering frontline healthcare to local people and robust academic training. So do the members of the New Zealand Medical Association, the New Zealand Nurses Organisation and the Association of Salaried Medical Specialists, who have voiced substantial concerns.

Last November, the Association of Salaried Medical Specialists (which represents more than 4000 medical specialists and 90 per cent of the specialist workforce) opposed the TPP on the grounds that healthcare would suffer and called on the Government to at least undertake an independent health impact assessment.

Groser claimed our concerns were based on ideology. Well, as doctors, our ideology is that the tobacco industry should have no right to claim payback for loss of profit when a government acts to control its product that kills.

Phillip Morris is suing Australia for introducing plain packaging laws for tobacco products. We think that maintaining the ability of our government to enact protective laws without the threat of legal action from companies with very deep pockets is politically relevant.

Groser has claimed we are opposed to trade. This is not correct. We strongly support Pharmac, which utilises market competition to deliver exceptional value with its medication purchasing strategies.

Pharmac's 2014 annual review indicates it saved more than $1.2 billion in that year alone. Pharmac is able to buy medicines at an average discount of about two-thirds.

Changes to intellectual property rules within the TPP will increase monopoly power – the opposite to what is achieved by market forces. There is evidence that this has already happened in other countries.

The TPP will limit Pharmac's effectiveness, prove extremely expensive and divert money away from other already-overstretched healthcare services.

It is well reported that financial shortfalls are already affecting many DHBs and that many patients miss out on important medical and surgical interventions or spend considerable times on waiting lists.

The new legal rules that will most affect Pharmac are the extension of data exclusivity for biological medications, the introduction of patent linkage and the ability for pharmaceutical corporations to legally challenge Pharmac's decisions.

Seven of Pharmac's 20 highest-expenditure medicines are from the group of medicines called biologicals – namely adalimumab, trastuzumab, etanercept, insulin glargine, rituximab, pneumococcal vaccine, and epoietin beta.

They cost Pharmac $163m last year. Under TPP these drugs will cost at least another $25m to $50m a year. New biologicals could be extremely – perhaps prohibitively – expensive.

We believe that keeping the cost of medicines reasonably affordable is politically relevant.

We are a broad coalition of healthcare experts and aim to protect not only equity and access in healthcare but also national sovereignty for sensible policy-making.

If we are ultimately considered "politically irrelevant", we have to ask, what in the minister's estimation is politically relevant?

Doctors Erik Monasterio, Philip Pattemore and George Laking are senior medical specialists.