P039 Consideration of guanfacine for addition to the ADHD pathway following review of effectiveness
Authors: Webb Liz 
Published: June 2019

Background

Intuniv (guanfacine hydrochloride) is indicated for the treatment of attention deficit hyperactivity disorder (ADHD) in children and adolescents 6-17 years old for whom stimulants are not suitable, not tolerated or have been shown to be ineffective. In June 2016 the decision by All Wales Medicines Strategy Group (AWMSG) was that cost effectiveness had not been proven making it difficult to add the drug to our local prescribing formulary. Initially Individual Patient Funding Requests (IPFR) were submitted but this was not a sustainable approach. Following discussion at Women and Children’s Clinical Board Medicines Management Group it was agreed that a Non Formulary request could be used if each was approved by the Community Child Health Clinical Director and Directorate Pharmacist and both stimulants and atomoxetine had been tried unless contraindicated. This would allow us to gain much needed experience of using the drug and allow us to evaluate where it should sit within the treatment pathway.

Aim

To review the effectiveness of guanfacine in all children and young people for whom an IPFR or Non Formulary Form had been approved over 12 months May 2017 – April 2018

Methods

Children and young people were identified from the IPFR and Non Formulary forms. The forms provided information on reasons for considering guanfacine, clinician and patient identifiers, other data, date, reason and age at initiation was collected from medical notes and electronic clinical system (PARIS). The maintenance dose, any side effects and assessment of effect as well as reason and date stopped, if relevant were recorded.

Results

22 children and young people were reviewed consisting of 6 IPFR’s and 16 non formulary forms. 100% of patients had previously taken stimulants and atomoxetine. 5 patients never started guanfacine.

17 patient’s notes were reviewed. Average age at initiation was 13 (range 8-17).

9 (53%) patients have continued on guanfacine and the average maintenance dose was 3 mg daily (range 1–4 mg). 6 (35%) had a good response, 1 (6%) had some benefit, 2 (12%) limited benefit but better than no medication.

8 (47%) patients stopped treatment. 4 (24%) stopped due to increased challenging behaviour/anger/character changes, 1 (6%) borderline BP and dizziness, 1(6%) no response, 1 (6%) substance misuse and non-compliance, 1 (6%) vomiting, 76% were requested by CAMHS clinicians, 24% requested by community paediatricians.

Conclusion

Guanfacine is an effective alternative treatment for some ADHD patients with a different mode of action and different side effect profile. A small number of patients would benefit from its inclusion in the Formulary. The children and young people on guanfacine had already had stimulants and atomoxetine unless contraindicated; historically the alternative for them has been non pharmacological interventions. Half of the patients on guanfacine received benefit. An Implementation Planning Document (IPD) has been submitted to the Clinical Board requesting addition to the formulary as a Hospital Only (HO) medicine and inclusion in the ADHD pathway. AWMSG are not due to review guanfacine.