Loratadine

Letter of 19th October 2001 on loratadine

GP practices
Community pharmacies
Walk-In Centres
Trust Heads of Pharmacy
Chairs of Trust Drug and Therapeutics Committee/Trust Medical Directors

Dear Colleague

IMPORTANT - DRUGS NEARING THE END OF THEIR PATENT LIFE:
THE CASE OF LORATADINE ('CLARITYN')

Schering-Plough wrote to GPs early last month to provide three months notice of discontinuation of 'Clarityn' (loratadine 10mg) tablets on prescription. The Area Prescribing Committee (APC) considered this matter in detail on 14th September and agreed that local prescribers and pharmacists should be fully informed of the background to this and, in future, similar withdrawals. This letter has also been e-mailed to all GP practices.

It is available, together with all previous APC guidance at http://nww.bury-roch-ha.nhs.uk/apc

The APC website also contains a summary of all published NICE guidance.

Why is Clarityn being withdrawn ?

Schering Plough quotes commercial reasons for the discontinuation of prescription packs of Clarityn tablets on 3 December 2001. In an article in the Pharmaceutical Journal on 15 September 2001, a spokeswoman for Schering Plough acknowledged that it would be "ridiculous" to deny that the expiry of the patent on loratadine was not a consideration. Loratadine is protected by patent until November 2002.

Is 'Neo-Clarityn' better than 'Clarityn' ?

No. Both 'Clarityn' and 'Neo-Clarityn' are licensed for the relief of symptoms associated with seasonal allergic rhinitis and chronic idiopathic urticaria. The European Public Assessment Report summarises the findings of four efficacy studies on desloratadine and concludes that desloratadine 5mg is probably not superior to loratadine 10mg for seasonal allergic rhinitis.

What action does Schering Plough suggest ?

In the Pharmaceutical Journal, Schering Plough were quoted as stating that "Following that date [December 3, 2001], loratadine prescriptions can be replaced by desloratadine". Schering Plough also supplies NeoClarityn (desloratadine). (Note: pharmacists will not be able to substitute desloratadine when loratadine has been prescribed and will have to return prescriptions for loratadine to the prescriber for amendment).

Will generic loratadine still be available during 2002 ?

Yes. Schering Plough is not withdrawing the Product Licence for Clarityn. Over the counter (OTC) preparations continue to be available, together with Clarityn Syrup. There are a large number of Product Licence applications for generic loratadine lodged with the Medicines Control Agency, which would become available from the expiry of the Supplementary Protection Certificate in November 2002. Recent experience has shown that the inclusion of a generic product within the Drug Tariff has seen the price of the generic product drop by 60-70% within twelve months of the expiry of the patent or SPC.

How much loratadine is prescribed ?

In the 12 months to June 2001 there were over 31 000 primary care prescriptions for loratadine in Bury and Rochdale at a basic NHS cost of Ł229 k (Table 1). The potential annual saving which would be expected from generic loratadine would be about Ł137k depending on the price of generic loratadine. The actual savings may be less than this if the loratadine market shrinks as a result of the manufacturer's current action.

	Items (000)	Cost (Ł 000 actual)	Potential saving* (Ł 000 actual))
BURY NORTH	8.8	65.5	39.3
BURY SOUTH	8.4	59.2	35.5
HEYWOOD & MIDDLETON	5.6	42.3	25.4
ROCHDALE	8.8	62.2	37.3
BURY and ROCHDALE	31.7	229.1	137.5

Table 1. Primary care prescribing of loratadine July 2000 to June 2001 * at expected generic loratadine prices

What are the options for prescribers

Do nothing and continue to prescribe loratadine. This would avoid the need to switch patients' treatment (and the resulting substantial workload for practices) but may cost significantly more in the short-medium term as prescriptions would be met by dispensing the OTC version which costs over Ł10 for 30x10mg tablets. The additional costs would be expected to be offset by price reductions when generic loratadine becomes available in late 2002.
Switch patients to desloratadine, as proposed by Schering Plough. Although cost-neutral at present, there would then be no opportunity for the NHS to benefit from the expected cost-savings from generic loratadine. In addition, desloratadine is not yet licensed for use in patients less than 12 years. Practices who are offered the services of a Schering Plough-sponsored nurse or other staff should bear in mind, as in all such cases, newly-developed guidance from the Area Prescribing Committee on Commercial Sponsorship.
Switch to another non-sedating antihistamine (Table 2). Until recently, cetirizine ('Zirtek') would have been a reasonable choice but an optical isomer, levocetirizine (the unpronounceable 'Xyzal') has been introduced. Although UCB Pharma have no current plans to withdraw 'Zirtek' before the patent expires in February 2002, it is a distinct possibility. Other non-sedating alternatives are fexofenadine and acrivastine. Mizolastine is not recommended as a first-line option due to its propensity to cause cardiac arrhythmias in susceptible patients.

Drug	Adult Dose	NHS cost for 30 days supply (Ł)	Seasonal allergic rhinitis	Perennial allergic rhinitis	Chronic idiopathic urticaria
Loratadine	10 mg once daily	7.57	Yes	Yes	Yes
Loratadine (OTC)	10 mg once daily	10.82	Yes	Yes	Yes
Loratadine syrup	2x5 ml daily	22.71	Yes	Yes	Yes
Desloratadine	5 mg once daily	7.57	Yes	No	Yes
Cetirizine	10 mg once daily	8.73	Yes	Yes	Yes
Fexofenadine	120 mg once daily	7.40	Yes	No	Yes*
Acrivastine	8 mg three times a day	5.15	Yes	Yes	Yes
Levocetirizine	5 mg once daily	7.45	Yes	Yes	Yes

These issues are relatively complex but have the potential to cause increased workload for practices and increased costs for the NHS. Please take the opportunity to discuss the options with your Prescribing Support Team. The tactic of substituting facsimile products for those approaching patent expiry is becoming more common. Local prescribing teams will be monitoring these closely and will be writing with more information and advice as appropriate.

Yours sincerely

MARK CAMPBELL
PHARMACEUTICAL ADVISOR
ON BEHALF OF BURY AND ROCHDALE AREA PRESCRIBING COMMITTEE

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HA Executive Management Team
PCO Chief Executives, Bury and Rochdale
HA Pharmaceutical Advisors, Greater Manchester
Helen Allanson/Fraser Campbell, North West Regional Office