One year after US journalist James Foley was savagely murdered by Islamic State kidnappers, his family is campaigning to give future hostages a fighting chance of avoiding his fate.

After his death, Foley's parents joined press freedom activists and families of other American hostages to press Washington to review the way it deals with kidnappers.

And, buoyed by an outpouring of public shock and support in the wake of Foley's stage-managed and videotaped beheading, they have made some breakthroughs.

In June, President Barack Obama -- responding to criticism of US policy spearheaded by the Foley family -- changed existing procedures to deal with hostage-takings.

Families of missing Americans will have a single point of contact: a "fusion cell" uniting specialists from the FBI, CIA, State Department and other agencies.

And Obama, while not revoking a US policy of not making concessions to terrorists, has said families will not be prosecuted for discussing ransom demands with kidnappers.

Foley's mother Diane will visit Washington next week with others campaigning for hostage families to check on the work of the cell and discuss the way ahead.

She and the activist organizations backing her campaign support the work that has been done, with one very important proviso: around 30 Americans are still held abroad.

"We're very hopeful for it, but we don't have any Americans home yet," Diane Foley told AFP, thanking White House officials for ordering the review and beginning to act on it.

"We've done a very in-depth review with hostage families... but the real proof of its success will be the return of an American hostage," she said.

Foley, a 40-year-old freelance journalist, was murdered by an Islamic State jihadist on August 19 last year, outside the group's Syrian base in Raqa.

Two weeks later, his fellow US hostage Steven Sotloff was killed in the same manner, again on camera and by the same British-accented IS executioner.

- Disturbing details -

Propaganda footage of their deaths triggered global revulsion and threw light on the horrors facing those living under the Islamic State group's rule in its self-declared "caliphate."

But it also betrayed a stark difference in the fates of hostages from some European nations and of those from the United States and Britain.

Reporters from France and Spain who had been held with Foley and Sotloff had been released alive, reportedly after large ransoms were paid.

Britain and the United States do not pay ransoms. British aid workers David Haines and Alan Henning were killed just weeks after Foley and Sotloff.

Foley's family complained after his death that US officials had threatened to prosecute them if they tried to pay a ransom.

On Wednesday, White House National Security Council spokesman Peter Boogaard noted that already in June, President Obama had said: "As a government... we must do better."

Boogaard added: "We are grateful for the courage and generosity of the Foleys and the other families and former hostages for their engagement and assistance with the hostage policy review and we are committed to implementing the reforms going forward."

In June, Obama restated US policy to deny kidnappers the benefits of ransom, prisoner releases or policy changes but added that "no concessions does not mean no communications."

Press watchdogs joined the families in welcoming the results of the review.

But they too are keen to see results for the remaining US hostages around the world, such as reporter Austin Tice, who was captured in Syria three years ago.

"There was definitely a lot to improve," said Delphine Halgand, US director of Reporters Without Borders.

Since Foley's death, disturbing details have surfaced of the last days of another US hostage in Syria, 26-year-old humanitarian worker Kayla Mueller.

US officials believe she was repeatedly raped by her captors, including by IS leader Abu Bakr al-Baghdadi, before she was killed.

Mueller's parents complained in a CBS News interview that the administration had put its policy of not negotiating ransoms ahead of their daughter's life.

- Right direction -

In December, US journalist Luke Somers and South African teacher Pierre Korkie died after their Al-Qaeda captors shot and wounded them during a rescue attempt in Yemen by US commandos.

Korkie's supporters complained after the raid that they had been on the verge of negotiating his release.

Despite these setbacks, activists believe US policy is moving in the right direction.

"Real progress will come when a US captive will come back, and that's why we are working every day for the safe return of Austin Tice," Halgand said.

For her part, Diane Foley sees the mobilization in Washington as a tribute to the work of her slain son.

"It's really very hopeful that the lives of Jim and Steven and others won't be in vain," she told AFP.