Skip to main content

Advertisement

Log in

Dosage Form Development, in Vitro Release Kinetics, and in Vitro–in Vivo Correlation for Leuprolide Released from an Implantable Multi-reservoir Array

  • Research Paper
  • Published:
Pharmaceutical Research Aims and scope Submit manuscript

Abstract

Purpose

Implanted multi-reservoir arrays improve dosing control relative to osmotic pumps or polymer depots. The limited reservoir volume requires concentrated formulations. This report describes the development of a stable solid phase formulation of leuprolide acetate for chronic in vivo delivery from a multi-reservoir microchip and examines the correlation between in vitro release kinetics and serum pharmacokinetics.

Materials and Methods

Concentrated formulations (>10% w/v) were prepared using small volume processing methods. Drug yield, release kinetics, and formulation stability were evaluated in vitro by HPLC. The correlation between in vitro and in vivo kinetic data was determined for a solid formulation by direct comparison of data sets and using absorption kinetics calculated from the Wagner–Nelson equation.

Results

High yield and the control of release kinetics by altering peptide formulation or reservoir geometry were demonstrated. Lyophilized leuprolide in a soluble solid matrix exhibited reproducible release kinetics and was stable (>95% leuprolide monomer) after 6 months at 37°C. A strong correlation was found between in vitro release kinetics and in vivo absorption by direct comparison of data sets and using the Wagner–Nelson absorption (slopes of 1.01 and 0.91; R2 0.99).

Conclusions

Reproducible releases of a stable solid leuprolide formulation from a multi-reservoir microchip were achieved in vitro. Chronic pulsatile release was subsequently performed in vivo. Comparison of in vitro and in vivo data reveals that pharmacokinetics were controlled by the rate of release from the device.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12

Similar content being viewed by others

Abbreviations

DMSO:

dimethylsulfoxide

IVIVC:

in vitro–in vivo correlation

PEG:

polyethylene glycol

PK:

pharmacokinetic

RSD:

relative standard deviation

SD:

standard deviation

References

  1. M. Goldberg and I. Gomez-Orellana. Challenges for the oral delivery of macromolecules. Nat. Rev. Drug Discovery 2:289–295 (2003).

    Article  CAS  Google Scholar 

  2. R. Langer. Where a pill won’t reach. Sci. Am. 288:50–57 (2003).

    Article  PubMed  Google Scholar 

  3. J. B. Weitzman. Electronic medical devices: a primer for pathologists. Arch. Pathol. Lab. Med. 127:814–825 (2003).

    PubMed  Google Scholar 

  4. M. Scavini, et. al. Catheter survival during long-term insulin therapy with an implanted programmable pump. Diabetes Care 20:610–613 (1997).

    Google Scholar 

  5. J. L. Selam, P. Micossi, F. L. Dunn, and D. M. Nathan. Clinical trial of programmable implantable insulin pump for type I diabetes. Diabetes Care 15:877–885 (1992).

    Article  PubMed  CAS  Google Scholar 

  6. M. M. Tan, C. A. Corley, and C. L. Stevenson. Effect of gelation on the chemical stability and conformation of leuprolide. Pharm. Res. 15:1442–1448 (1999).

    Article  Google Scholar 

  7. S. C. Hall, M. M. Tan, J. J. Leonard, and C. L. Stevenson. Characterization and comparison of leuprolide degradation profiles in water and dimethyl sulfoxide. J. Pept. Res. 53:432–441 (1999).

    Article  PubMed  CAS  Google Scholar 

  8. C. L. Stevenson, J. J. Leonard, and S. C. Hall. Effect of peptide concentration and temperature on leuprolide stability in dimethyl sulfoxide. Int. J. Pharm. 191:115–129 (1999).

    Article  PubMed  CAS  Google Scholar 

  9. J. M. Maloney, et al. Electrothermally activated microchips for implantable drug delivery and biosensing. J. Control. Release 109:244–255 (2005).

    Article  PubMed  CAS  Google Scholar 

  10. J. H. Prescott, et al. Chronic, programmed polypeptide delivery from an implanted, multireservoir microchip device. Nat. Biotechnol. 24:437–438 (2006).

    Article  PubMed  CAS  Google Scholar 

  11. V. R. Uppoor. Regulatory perspectives on in vitro (dissolution)/in vivo (bioavailability) correlations. J. Control. Release 72:127–132 (2001).

    Article  PubMed  CAS  Google Scholar 

  12. J. G. Wagner and E. Nelson. Percent absorbed time plots derived from blood level and/or urinary excretion data. J. Pharm. Sci. 52:610–611 (1963).

    Article  PubMed  CAS  Google Scholar 

  13. R. M. Iskakov, A. Kikuchi, and T. Okano. Time-programmed pulsatile release of dextran from calcium-alginate gel beads coated with carboxy-n-propylacrylamide copolymers. J. Control. Release 80:57–68 (2002).

    Article  PubMed  CAS  Google Scholar 

  14. S. Wolf and R. N. Tauber. Silicon Processing for the VLSI Era Vol. 1 Process Technology. Lattice, Sunset Beach, CA, 1986.

    Google Scholar 

  15. H. Okada, et al. Pharmacokinetics of once-a-month injectable microspheres of leuprolide acetate. Pharm. Res. 8:787–791 (1991).

    Article  PubMed  CAS  Google Scholar 

Download references

Acknowledgements

We would like to thank all members of the MicroCHIPS team that supported this work. Special recognition is given to David Brancazio, David Lanteigne, Christina Pelta, and Michael Shannon for their contributions.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to James H. Prescott.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Prescott, J.H., Krieger, T.J., Lipka, S. et al. Dosage Form Development, in Vitro Release Kinetics, and in Vitro–in Vivo Correlation for Leuprolide Released from an Implantable Multi-reservoir Array. Pharm Res 24, 1252–1261 (2007). https://doi.org/10.1007/s11095-007-9243-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11095-007-9243-2

Key words

Navigation