AUTH/1833/5/06 - AstraZeneca v GlaxoSmithKline

CONCEPT study leavepiece

  • Received
    07 May 2006
  • Case number
    AUTH/1833/5/06
  • Applicable Code year
    2006
  • Completed
    24 July 2006
  • Breach Clause(s)
    7.2 (x 2) and 7.3 (x 2)
  • Sanctions applied
    Undertaking received
  • Additional sanctions
  • Appeal
    No appeal
  • Review
    Published in the November 2006 Review

Case Summary

AstraZeneca complained that a leavepiece issued by Allen & Hanburys, part of GlaxoSmithKline, did not present a fair and balanced account of the CONCEPT (CONtrol CEntred Patient Treatment) study which had compared stable dosing of GlaxoSmithKline’s product Seretide (salmeterol/fluticasone propionate) with symptom led (variable) dosing of AstraZeneca’s product Symbicort (formoterol/budesonide) in the management of asthma. The leavepiece implied that Seretide was compared with clinically equivalent doses of Symbicort as it did not explicitly state that like-for-like steroid doses were not used (82% Symbicort patients were stepped down to the lowest possible dose, compared with all Seretide patients being maintained at 500mcg per day). The leavepiece did not explicitly state that in the Symbicort arm the steroid dose could only be increased in response to symptoms, thus predetermining a higher symptom level in this group. The leavepiece did not reflect the balance of the evidence in that it did not refer to the results of the SUND study (where comparable steroid doses were used, which resulted in significantly fewer exacerbations in the Symbicort arm).

The CONCEPT study had consisted of a 2 week run-in, a 4 week stabilisation phase and a 48 week variable maintenance phase. During the 4 week stabilisation phase patients remained on either Seretide 250mcg bd or Symbicort 200mcg 2 puffs bd which equated to comparing a daily dose of 500mcg fluticasone with 800mcg budesonide (delivered via a turbohaler device) respectively. AstraZeneca stated that these doses were approximately equivalent.

Following 4 weeks on approximately equivalent doses patients entered the variable maintenance phase if they were completely symptom free. During the variable maintenance phase, Seretide patients remained on fixed Seretide 250mcg 1 inhalation bd. Symbicort patients could adjust their therapy according to a predefined treatment plan; they could halve their dose and subsequently step up or down as indicated by the presence or absence of various asthma symptoms and changes in morning peak expiratory flow measurements. If Symbicort patients were well controlled they were instructed to further reduce the dose to only 1 inhalation once daily in the evening which equated to a daily steroid dose of only 200mcg of budesonide. This was important as Seretide patients remained on a fixed daily dose of 500mcg fluticasone.

Results showed that during the variable maintenance phase 82% of Symbicort patients stepped down to 1 inhalation per day at some time during the trial. Only when they developed

symptoms were they instructed to step up the dose to regain asthma control. Thus the majority of Symbicort patients were instructed to down titrate to the lowest possible maintenance dose of inhaled steroid and remain on this dose until they developed asthma symptoms. It was therefore not surprising that these patients experienced more asthma symptoms and exacerbations compared to those taking comparatively higher steroid levels of Seretide 250mcg bd.

The dose for dose steroid comparison chosen for this trial was alleged to be unfair and likely to have significantly influenced the efficacy results. In order to fairly compare two different treatment approaches for asthma using either a fixed or an adjustable dosing regime one would need to have compared a more equivalent overall dose for dose steroid comparison.

Furthermore, the summaries of product characteristics (SPCs) for Symbicort and Seretide supported a reduction in dosing to 1 puff daily. The CONCEPT study design did not allow well controlled Seretide patients to step down to once daily dosing as recommended in the SPC.

Restricting once daily dosing to Symbicort created an unfair dose comparison increasing the probability of a favourable outcome for patients taking twice daily Seretide.

AstraZeneca stated that it had conducted 8 studies, involving over 10,000 patients, using Symbicort as an adjustable dosing regime whereby patients could adjust therapy according to a patient asthma management plan. In all of these trials patients could down titrate their Symbicort dose if well controlled to a minimum dosage of 2 inhalations per day. In those trials comparing adjustable

maintenance dosing with fixed dosed Symbicort, adjustable maintenance dosing provided at least as good or superior asthma control compared to fixed 51174 Code Review NOV 11/12/06 12:27 Page 25 dose Symbicort but at reduced overall medication doses. AstraZeneca noted in particular that the SUND study demonstrated that Symbicort

adjustable maintenance dosing was equivalent in terms of achieving the primary endpoint of odds of achieving a well-controlled asthma week compared to fixed dose Seretide and significantly more effective at reducing the clinically important secondary endpoint of severe exacerbations.

AstraZeneca submitted that the previous studies, in contrast to the CONCEPT study, had shown

adjustable dosing with Symbicort to be either as or more efficacious than using fixed dose maintenance therapy. This was because the dosing regimes used in the previous studies had been more equivalent.

Finally, recent research indicated that in normal clinical practice only 0.3% of patients were instructed by their health professional to take Symbicort at all strengths 1 puff once daily. Hence the doses of Symbicort used in the CONCEPT study did not reflect UK clinical practice.

AstraZeneca noted that the CONCEPT study design depicted in the leavepiece did not show that the majority of Symbicort patients were down-titrated to one inhalation a day. This was important as the relative doses of corticosteroid used in the maintenance part of the study were a critical determinant in the evaluation of relative efficacy.

Hence the statement regarding once daily dosing in small font at the bottom was not sufficiently prominent nor did the page indicate the high percentage of Symbicort patients (82%) who were down-titrated to 1 inhalation daily at some point in the trial. Not including this data was clearly misleading and unfair and did not allow the reader to reach a balanced view.

AstraZeneca alleged that the claim ‘Seretide stable dosing achieves superior asthma control compared to formoterol/budesonide symptom led dosing’ was all encompassing, exaggerated and misleading and did not reflect fairly the body of clinical evidence.

Also the symptom led dosing approach used in the study was not one that was used routinely in clinical practice.

The Panel noted that CONCEPT was a comparative study of two different treatment approaches for asthma – fixed maintenance dosing with Seretide or adjustable maintenance dosing with Symbicort.

Patients in the study were previously symptomatic on either 200-500mcg inhaled corticosteroid plus long acting beta2 agonist or >500-1000mcg inhaled corticosteroid alone. Patients were initially stabilized, over four weeks, on Seretide 250 1 puff twice daily (total daily dose (tdd) salmeterol 100mcg/fluticasone 500mcg) or Symbicort 2 puffs twice daily (tdd formoterol 24mcg/budesonide 800mcg twice daily). During this stabilization phase, when both groups received fixed doses, the percentage of symptom-free days was similar between the two treatments. Having been stabilized over 4 weeks, patients in the Symbicort group were instructed to halve their dose to 1 puff twice daily (tdd formoterol 12mcg/budesonide 400mcg). At subsequent clinic visits patients who continued to be controlled could halve the dose again to 1 puff daily (formoterol 6mcg/budesonide 200mcg daily).

Such low dosing was not inconsistent with the Symbicort SPC. If after stepping down to this lowest dose patients subsequently lost control of their asthma, as defined by certain criteria, they were instructed to go back to not less than 1 puff twice daily (tdd formoterol 12mcg/budesonide 400mcg) throughout the rest of the 52 week period. The study was not a comparison of steroid dose per se.

During the course of the study 83.1% of patients in the Symbicort group stepped down their dose to 1 puff daily at some time and 41.6% increased their dose to 4 puffs twice daily for 7-14 days at least once. Over the 52 week treatment period the mean daily dose of fluticasone (from Seretide two puffs daily) was 463mcg and the mean daily dose of budesonide (from adjustable dosing of Symbicort) was 480mcg. Diary card data showed that Symbicort patients used a mean of 1.8 inhalations daily (equivalent to 360mcg budesonide).

The Panel noted that the leavepiece did not detail the mean daily dose of product or the mean daily number of inhalations. Further the leavepiece gave no details as to how patients, in practice, had adjusted the dose of Symbicort. It was thus difficult for readers to fully understand the clinical significance of the results. The Panel considered that in this regard the leavepiece was misleading.

Breaches of the Code were ruled.

The Panel noted AstraZeneca’s comments regarding the design of the CONCEPT study, the fact that its results seemed to contradict other studies and that the symptom led dosing approach used was not one that was routinely used in clinical practice.

However, other studies had been open-label as opposed to the CONCEPT study which was doubleblind. Additionally the CONCEPT study had allowed Symbicort to be dosed at 1 puff daily which, although lower than in other studies, was nonetheless consistent with the Symbicort SPC. In that regard, whilst noting its ruling above, the Panel did not consider that claims such as ‘Seretide stable dosing achieves superior asthma control compared to formoterol/budesonide symptom led dosing’ regarding the symptom led dosing of Symbicort per se were misleading. No breaches of the Code were ruled.