Disability campaigners from Shropshire will bring a legal challenge against the Director of Public Prosecutions, over current assisted suicide laws.
The 1961 Suicide Act makes it a criminal offence to assist or encourage suicide. The DPP has a discretion on whether to prosecute.
In October 2014, Alison Saunders amended the policy, making the prosecution of healthcare professionals in assisted suicide cases less likely.
Mr and Mrs Kenward from Aston on Clun say that the change in wording makes it less likely that healthcare professionals will be prosecuted.
They will travel to London today to seek permission to appeal against the High Court ruling.
Nikki Kenward was stricken by Guillain-Barre Syndrome in 1990 and left almost completely paralysed for five months, only able to blink her right eye.
The former theatre manager, who now uses a wheelchair, said that the High Court's decision was "bizarre" and "leaves vulnerable people at risk".