Intellectual property remains a major sticking point in negotiations for the 12-country Trans Pacific Partnership Agreement (TPP).
The issue is believed to remain unresolved following recent talks in Hawaii between negotiators representing the countries that comprise 40 per cent of the world's economy.
The US is understood to be pushing for longer data exclusivity periods, with Australia one of several countries opposing the move.
Australia currently maintains a 5-year data exclusivity period.
A recent open letter to the Australian Parliament from AusBiotech and two other leading research-based organisations, dismissed claims that extending data exclusivity would lead to higher medicine prices.
According to the groups, "No change to intellectual property law can increase the price that a consumer would pay for any PBS medicine."
Trade Minister Andrew Robb also dismissed the claims, describing them as part of a pre-meditated scare campaign.
Another potential barrier to finalising the TPP is a decision by the US Congress on whether it will pass Trade Promotion Authority (TPA) legislation.
Under the TPA, the Congress defines US negotiating objectives and priorities for trade agreements. Once finalised, Congress gives an agreement an up or down vote, without amendment.
The TPA has existed in some form since 1974.