Two strengths of BMS-309403 capsules were developed from a common stock granulation. Dissolution testing of the capsules was conducted utilizing the USP apparatus 2 (paddle) with a neutral pH dissolution medium. Unexpectedly, the lower-strength capsules exhibited slower dissolution than the higher-strength capsules filled with the same stock granulation. Higher variability was also observed for the lower-strength capsules. This was found to be mainly caused by a low fill weight in a relatively large size hard gelatin capsule shell. Instead of bursting open, some gelatin capsule shells softened and collapsed onto the granulation, which delayed the release of the active drug. The problem was aggravated by the use of coil sinkers which hindered the medium flow around the capsules. Switching from the gelatin capsule shells to the HPMC (hydroxypropyl methylcellulose) shells reversed the dissolution rate ranking between the two capsule strengths. However, both dissolved at a slower rate initially than the gelatin capsules due to the inherent dissolution rate of the HPMC shells at pH 6.8. Notably, the HPMC shells did not occlude the granulation as observed with the gelatin shells. The study demonstrated that the dissolution of capsule formulations in neutral pH media was significantly affected by the fill weight, sinker design, and capsule shell type. Careful selection of these parameters is essential to objectively evaluate the in vitro drug release.