THE POSSIBILITY FOR AVOIDANCE OF MUTUAL PHARMACOKINETIC INTERACTION BETWEEN SILDENAFIL AND BOSENTAN, STAGGERING ADMINISTRATION TIMING OF THE TWO DRUGS

THE POSSIBILITY FOR AVOIDANCE OF MUTUAL PHARMACOKINETIC INTERACTION BETWEEN SILDENAFIL AND BOSENTAN, STAGGERING ADMINISTRATION TIMING OF THE TWO DRUGS - THE POSSIBILITY FOR AVOIDANCE OF MUTUAL PHARMACOKINETIC INTERACTION BETWEEN SILDENAFIL AND BOSENTAN, STAGGERING ADMINISTRATION TIMING OF THE TWO DRUGS

Status

Active, not recruiting

Phases

Phase 4

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000002566

Enrollment

Registered

2009-10-01

Start date

2009-02-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pulmonary Hypertension

Interventions

&lt

Intervention 1&gt

C, A, C, B A: Bosentan administration three hours after sildenafil

seven days B: Sildenafil administration three hours after bosentan

seven days C: Simultaneous administration of sildenafil and bosentan

seven days &lt

Intervention 2&gt

C, B, C, A A: Bosentan administration three hours after sildenafil

seven days

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1 Patients of pulmonary hypertention of WHO performance classfication 3 and 4. 2 Patients who continuously take both bosentan and sildenafil.

Exclusion criteria

Exclusion criteria: 1 Patients who entail obvious adverse side-effects of either bosentan or sildenafil. 2 Patients who hardly continue taking bosentan or sildenafil for other reasons.

Design outcomes

Primary

Measure	Time frame
Plasma cancentration of sildenafil and its primary metabolite N-desmethylsildenafil of the following blood samples; before dose, and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10 and 12 h post dose of the first sildenafil on the day.	—

Secondary

Measure	Time frame
# Plasma concentration of Bosentan of the same points above. # Blood pressure of before dose, 1 and 3 h post dose of the first sildenafil on the day.	—

Countries

Japan

Contacts

Public ContactSachiko Miyakawa

Hamamatsu University School of Medicine Clinical Pharmacology and Therapeutics

053-435-2385

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026