Oxybutynin, transdermal patches, 36 mg (releasing approximately 3.9 mg per 24 hours), 8, Oxytrol® , March 2009
Public summary document for Oxybutynin, transdermal patches, 36 mg (releasing approximately 3.9 mg per 24 hours), 8, Oxytrol® , March 2009
Page last updated: 03 July 2009
Public Summary Document
Product: Oxybutynin, transdermal patches, 36 mg
(releasing approximately 3.9 mg per 24 hours), 8,
Oxytrol®
Sponsor: Hospira Australia Pty Ltd
Date of PBAC Consideration: March 2009
1. Purpose of Application
The submission sought a Restricted Benefit listing for the
treatment of urge urinary incontinence or urgency due to detrusor
instability in a patient who cannot tolerate or swallow oral
oxybutynin.
2. Background
The PBAC had rejected submissions to list transdermal oxybutynin on two previous occasions,
at its meetings in March and November 2008, on the basis of uncertain comparative
clinical effectiveness and the resulting uncertain cost-effectiveness.
A copy of the Public Summary Document (PSD) for the March and November 2008 PBAC consideration
of oxybutynin is available from the web site at:http://www.health.gov.au/internet/main/publishing.nsf/Content/public-summary-documents-by-meeting
3. Registration Status
Oxybutynin transdermal patch was TGA registered on 10 May 2007 for
the treatment of overactive bladder with symptoms of urinary
frequency, urgency or incontinence or any combination of these
symptoms.
4. Listing Requested and PBAC’s View
Restricted Benefit
Urge urinary incontinence or urgency due to detrusor instability in
a patient who cannot tolerate oral oxybutynin, or who cannot
swallow oral oxybutynin.
For PBAC’s view see Recommendation and
Reasons.
5. Clinical Place for the Proposed Therapy
Transdermal oxybutynin represents a treatment option for patients
with urge urinary incontinence or urgency, in patients who are
unable to tolerate the oral dose form.
6. Comparator
As previously, the submission nominated placebo as the main
comparator.
7. Clinical Trials
No new clinical data were presented in this resubmission compared
with the November 2008 submission.
Please see November 2008 Public Summary Document.
8. Results of Trials
Please see November 2008 Public Summary Document.
9. Clinical Claim
As previously, the submission claimed that transdermal oxybutynin
was more effective than placebo, but was associated with more
adverse events (application site reactions).
10. Economic Analysis
The submission presented the effect of a price reduction on the
modelled cost-effectiveness of transdermal oxybutynin.
The main concern with the previous economic analysis was not the
incremental cost-effectiveness ratio (ICER) per se. Based
on the clinical data, the ICER was calculated as < $15,000 per
quality-adjusted life year (QALY). The primary source of concern
was the large uncertainty associated with the point
estimates.
The price reduction proposed by the re-submission reduced the
uncertainty. The chance that transdermal oxybutynin resulted in
worse outcomes had reduced from 40.7% to 27%.
The incremental cost per extra QALY gained of < $15,000 based on
the revised price was considered acceptable by the PBAC.
11. Estimated PBS Usage and Financial Implications
The resubmission estimated the likely net cost to the PBS of <
$10 million in Year 5.
The PBAC noted that there is potential for use outside the
requested restriction.
12. Recommendation and Reasons
The PBAC recommended the listing of oxybutynin transdermal patches
on the PBS for treatment of detrusor overactivity in a patient who
cannot tolerate oral oxybutynin, or who cannot swallow oral
oxybutynin on the basis of acceptable cost effectiveness over
placebo.
The PBAC noted that the primary cause of concern from the previous
submission was the large uncertainty associated with the relative
risk point estimate for achieving complete continence. The
Committee agreed that the price reduction offered by the sponsor
reduced the associated uncertainty around this point estimate, with
the chance that transdermal oxybutynin is more effective and less
costly over placebo (i.e., results in cost-saving and better
outcomes) increasing, and the chance that transdermal oxybutynin
results in worse outcomes reducing from 40.7% to 27%. The
incremental cost per extra QALY gained of < $15,000 based on the
revised price was considered acceptable by the PBAC.
The PBAC noted that there is potential for use outside the
requested restriction.
Recommendation
OXYBUTYNIN, transdermal patches, 36 mg (releasing approximately 3.9
mg per 24 hours), 8
Restriction:
Restricted Benefit
Detrusor overactivity in a patient who cannot tolerate oral
oxybutynin, or who cannot swallow oral oxybutynin.
Max. Qty: 1
Repeats: 5
13. Context for Decision
The PBAC helps decide whether and, if so, how medicines should be
subsidised in Australia. It considers submissions in this context.
A PBAC decision not to recommend listing or not to recommend
changing a listing does not represent a final PBAC view about the
merits of the medicine. A company can resubmit to the PBAC or seek
independent review of the PBAC decision.
14. Sponsor’s Comment
Hospira welcomes the PBAC’s decision to recommend PBS listing
for Oxytrol, and increase the reimbursed options available to
patients suffering urge urinary incontinence and urgency.
