AUTH/1825/4/06 - ProStrakan v Shire

Calcichew-D3 Forte journal advertisement

  • Received
    06 April 2006
  • Case number
    AUTH/1825/4/06
  • Applicable Code year
    2006
  • Completed
    04 June 2006
  • Breach Clause(s)
    7.2 and 7.3
  • Sanctions applied
    Undertaking received
  • Additional sanctions
  • Appeal
    No appeal
  • Review
    Published in the August 2006 Review

Case Summary

ProStrakan complained about a journal advertisement for Calcichew-D3 Forte (calcium carbonate, colecalciferol) issued by Shire. The claim at issue, ‘Chew Calcichew-D3 Forte for Ten Seconds for a pleasant surprise. In a comparative study, Calcichew-D3 Forte was preferred over Adcal-D3 by 80% of patients’, was referenced to Rees and Howe (2001).

ProStrakan alleged that the claim was unfair and misleading.

Calcichew-D3 Forte was a chewable tablet containing 1250mg calcium carbonate (equivalent to 500mg of elemental calcium) plus 400 IU vitamin D3. Adcal-D3 was a chewable tablet containing 1500mg calcium carbonate (equivalent to 600mg of elemental calcium) plus 400 IU cholecalciferol (vitamin D3).

Rees and Howe was a randomised, investigator-blind, crossover, multicentre study of seven days’ treatment in 102 patients ≥ 60 years already receiving daily calcium and vitamin D supplements. At the time of recruitment 64% had been established on Calcichew-D3 Forte; the proportion of patients already on Adcal-D3 was unknown, although its market share at the time was 4-8%. This was important as the trial was open from the patients’ perspective and the tablets were quite different in terms of calcium carbonate content and this could have a significant impact on the results as calcium carbonate contributed the vast majority of the bulk of the tablet. Assessment of preference was determined through the use of a questionnaire using a visual analogue scale. The results were statistically in favour of the Calcichew-D3 Forte, with a preference of 79.8%. ProStrakan stated that there were no explanations of the rationale for the questions within the study, nor the clinical relevance to the patient as this was a non-standardised questionnaire.

ProStrakan alleged that there might have been statistical differences generated, apparently using a methodology not pre-specified in the protocol, despite this the median values were very similar in most cases, with significant overlap in the range. On closer examination of the results, the questions appeared biased against a tablet containing more calcium carbonate eg chalky and gritty. This would naturally bias the study against Adcal-D3.

Currently there were two other combination supplements on the market, Cacit D3 (calcium 1250mg, vitamin D3 440 IU) and Calceos (calcium 1250mg, vitamin D3 440 IU), which were the same dose as Calcichew-D3 Forte. For a taste preference study to be fair a comparison between brands with the same constitution would seem fair.

In addition ProStrakan alleged that the claim would mislead readers into believing that preferred was not quantified, which could potentially lead the reader to believe that there was a compliance difference between the products, data for which had not been provided.

ProStrakan alleged that this unfair comparison of Adcal-D3 and Calcichew-D3 Forte was of significant importance clinically, as a substantial body of evidence demonstrated a clinical benefit for a 1200mg dose of calcium carbonate (Adcal-D3) compared with a 1000mg dose (Calcichew-D3 Forte).

This was misleading as the two products were not comparable and the claim was out of context. The relevant clinical papers and a review of this data were provided for context.

Section 5.1 of the Adcal-D3 summary of product characteristics (SPC) further reinforced the differences which stated that there was strong evidence that supplemental calcium and vitamin D3 could reduce the incidence of hip and other nonvertebral fractures. In a randomised placebo controlled study, 3270 patients treated with 1200mg elemental calcium and 800 IU vitamin D3 daily, ie, the same dose delivered by two tablets of Adcal-D3, the number of hip fractures was 43% lower (p=0.043) and the total number of non-vertebral fractures was 32% lower than among those who received placebo.

A positive effect on bone mineral density was also observed. The Calcichew-D3 Forte SPC contained the same data (Chapuy et al) stating the important dose was 1200mg/day of elemental calcium.

ProStrakan alleged that Rees and Howe and the subsequent claims were unfair and misleading, as the two products were not comparable in outcomes or dosing and the claim was out of context.

The Panel noted that the aim of Rees and Howe was to compare the acceptability of Calcichew-D3 Forte with Adacal-D3. Both products had similar indications and although they had different

constituents the Panel considered that it was not unreasonable to compare the two. Patients (n=102) took Calcichew-D3 for seven days followed by Adcal-D3 for seven days or vice versa. At the end of each study period patients used visual analogue scales to indicate palatability in terms of grittiness, chalkiness, taste (bitter or sweet), ease of chewing, ease of swallowing and stickiness of each product; there was no difference between the two with regard to taste. The five other parameters were statistically significantly in favour of Calcichew-D3 Forte. After the second study period patients were asked which treatment they preferred.

The Panel considered that most readers of the advertisement would assume that 80% of patients preferred Calcichew-D3 Forte to Adacal-D3 because they thought it tasted better. Women in the advertisement were pictured with a smile, the claim was positioned next to their mouth and the product logo incorporated a picture of lemons. In Rees and Howe, however, patients were asked to assess palatability in terms of grittiness, chalkiness, ease of chewing, swallowing and stickiness on teeth as well as taste. The Panel considered that the patients’ views on these other parameters had influenced their preference given that there was no difference between the two as to perception of taste.

The Panel queried whether the seven day treatment periods were long enough to assess medicines that were intended for long term use. All patients recruited into the study were already taking calcium supplements; 64% of them were established on Calcichew-D3 Forte.

The Panel was concerned that insufficient detail was given about what it was that patients preferred about treatment with Calcichew-D3 Forte compared to treatment with Adcal-D3. The claim implied that not only did patients prefer Calcichew-D3 Forte to Adcal-D3 but they also found it pleasant to take.

There was no data in that regard.

The Panel disagreed with Shire’s view that the data on efficacy evaluations and health economics were irrelevant to the current complaint which only dealt with the issue of patient preference. The Panel considered that in addition to palatability a patient’s knowledge of some of the efficacy evaluations and differences in clinical outcomes between two products might affect their preference for one or the other. Without such knowledge patients would be unable to express a genuine, well informed preference.

Overall the Panel considered that the claim at issue, ‘Chew Calcichew-D3 Forte for Ten Seconds for a pleasant surprise. In a comparative study, Calcichew-D3 Forte was preferred over Adcal-D3 by 80% of patients’, was a misleading comparison.

Thus the Panel ruled breaches of the Code.