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Clinical equivalence of two tablet formulations of felodipine

A placebo-controlled study of 24-hour blood pressure control and tolerability

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Objective: This study was performed to assess whether a new formulation of felodipine extended release (FER) tablets with a 9 mm diameter is similar to the presently used 11 mm diameter FER formulation with respect to antihypertensive effect and tolerability in patients with essential hypertension. A randomised, double-blind, placebo controlled, three-way cross-over study design was used.

Patients: Twenty-four patients with a supine diastolic blood pressure (DBP) of 95–115 mmHg after a 4-week placebo run-in period were given FER 5 mg 9 mm tablets, FER 5 mg 11 mm tablets and placebo in randomised order. The tablets were given once daily and each double-blind treatment period lasted for two weeks.

Methods: Twenty-four hour ambulatory blood pressure monitoring was performed at the end of each treatment period. The primary effect variable was mean DBP over 24 hours. Nineteen patients had 24-hour blood pressure data valid for analysis using an analysis of variance with patient, treatment, period and carry-over as factors.

Results: Both formulations of FER 5 mg tablets significantly reduced the mean 24-hour DBP compared to placebo. The 9 and 11 mm tablets resulted in, on average, 4.7 and 3.4 mmHg lower mean 24-hour DBP than placebo. There was, however, no significant difference between the two different FER formulations. Both FER formulations were well tolerated and similar to placebo in this respect.

Conclusion: Both FER 5 mg tablet formulations (9 and 11 mm diameter), given once daily, were clinically equivalent with respect to antihypertensive effect and tolerability in patients with mild to moderate essential hypertension.

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  1. 1.

    Ljung B (1985) Vascular selectivity of felodipine. Drugs 29 [Suppl 2]:46–58

  2. 2.

    Todd PA, Faulds D (1992) Felodipine. A review of the pharmacology and therapeutic use of the extended release formulation in cardiovascular disorders. Drugs 44:251–277

  3. 3.

    Elvelin L, Kennerfalk A, Elmfeldt D (1993) Tolerability and safety of felodipine. Cardiovasc Drug Rev 11:126–147

  4. 4.

    Weber MA, Goldberg Al, Faison EP, Lipschutz K, Shapiro DA, Nelson EB, Irvin JD (1994) Extended-release felodipine in patients with mild to moderate hypertension. Clin Pharmacol Ther 55:346–352

  5. 5.

    Bergstrand R (1990) A bioequivalence study of two reduced size felodipine ER tablet formulations. Data on file, Astra Haessle Report

  6. 6.

    Ahnoff M (1984) Determination of felodipine in plasma by capillary gas chromatography with electron-capture detection. J Pharmacol Biomed Anal 2:519–526

  7. 7.

    Blychert E, Wingstrand K, Edgar B, Lidman K (1990) Plasma concentration profiles and antihypertensive effect of conventional and extended-release felodipine tablets. Br J Clin Pharmacol 29:39–45

  8. 8.

    Blychert E (1992) Felodipine pharmacokinetics and plasma concentration vs effect relationships. Blood pressure 1 [Suppl 2]:1–30

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Correspondence to B. P. McGrath.

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McGrath, B.P., Watts, R.W. & Elmfeldt, D.B. Clinical equivalence of two tablet formulations of felodipine. Eur J Clin Pharmacol 49, 169–172 (1995). https://doi.org/10.1007/BF00192375

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Key words

  • Felodipine
  • Hypertension
  • extended release formulation
  • tolerability