In February last year, a group of people dressed as zombies took to the streets of Kuala Lumpur.

But they were not fancy-dress partygoers in a parade. Instead, they were marching against the Trans-Pacific Partnership (TPP), which they believe will cause medicine prices to spiral out of control.

The spectre of higher drug prices was discussed in Singapore, too, as there were fears that big pharmaceutical companies would successfully demand long 12-year patents that would give them a monopoly over next-generation medicine.

In the end, the period of exclusivity was cut to five years.

But the "zombies" in Malaysia are not alone. Demonstrations in TPP signatory countries, such as New Zealand, the United States and Japan, have taken place in recent years over related issues. Negotiations have been criticised for being conducted in secrecy; the full text of the pact was released only after an agreement was reached last month.

There were also concerns about corporate rights clashing with sovereign rights.

A country providing subsidised medicine to its citizens might be challenged by pharmaceutical giants that want to sell drugs at a price they want.

Liberalising farming sectors proved to be a hot issue, too. In Japan, rice farmers will lose part of their longstanding protection as the country will eventually allow 78,000 tonnes of tariff-free rice to be imported, about 1 per cent of its total production.

But Canada agreed to open up only a small percentage of its dairy market.

Indeed, Asia-Pacific Economic Cooperation secretariat executive director Alan Bollard notes that the TPP "has taken a very cautious approach on a range of agricultural production", and it remains an "under-exploited area".

So why do countries sign agreements such as the TPP knowing there will be pressure on certain industries?

"There's clearly going to be some sectors that will be harmed by it, but the judgment of every country has been that overall it's a benefit," Dr Bollard says of the TPP.

Opposition to free trade pacts usually comes from vested interests seeking to protect domestic industries, says SIM University senior lecturer Walter Theseira.

But in Singapore's case, most of what is consumed here is imported anyway.

"Hence, in many sectors, we do not have a significant domestic industry to protect, and in any case, protecting domestic industry is often inefficient, so overall we would have more to lose than to gain," he says.

In theory, the TPP should expose Singapore businesses to more stress because of competition from foreign firms.

However, "Singaporean firms are already adept at surviving in an environment in which they receive little protection from imports from abroad", says National University of Singapore economics associate professor Davin Chor.

The challenge, then, is in "developing products and business strategies that will allow them to ride the wave of export opportunities that the TPP should create".

Similarly, Association of Small and Medium Enterprises president Kurt Wee says local businesses have to take the time to study such free trade deals so they can tap them.

Opportunities include new operations and manufacturing bases, and overseas government procurement contracts opening up for bids. "Firms should try to plan a growth roadmap in tandem with when the TPP kicks in," he adds.

Mr Wee also says he has not sensed any trepidation among Singapore businesses so far over the TPP. "From a relative perspective, when you look at the other 11 TPP partners, we are in a good position to sell more and supply more overseas."