Real‐world dosing characteristics and utilization of parenteral treprostinil in the outpatient setting

Real‐world dosing and titration of parenteral (subcutaneous, SC; intravenous, IV) prostacyclin, a mainstay of pulmonary arterial hypertension (PAH) treatment, is not always consistent with prescribing information or randomized trials and has yet to be adequately characterized. The current study describes real‐world outpatient dosing and titration patterns over time, in PAH patients initiated on SC or IV treprostinil. A longitudinal, cross‐sectional analysis of medication shipment records from US specialty pharmacy services between 2009 and 2018 was conducted to determine dosing and titration patterns of SC or IV treprostinil in the outpatient setting beginning with the patient's first shipment. The sample for analysis included shipment records for 2647 patients (IV = 1040, SC = 1607). Although more patients were started on SC treprostinil than IV, median initial outpatient IV treprostinil dose (11 ng/kg/min at month on therapy one [MOT1]) was consistently and statistically significantly higher than initial outpatient SC dose (7.5 ng/kg/min at MOT1; p < 0.01). However, the SC treprostinil dose acceleration rate (DAR) was more aggressive from MOT1 to MOT6, MOT12, and MOT24, leading to a higher dose achieved at later timepoints. All between‐group DAR differences were statistically significant (p < 0.001). This study provides evidence that real‐world prescribing patterns of parenteral treprostinil in the outpatient setting differs from dosing described in pivotal trials, with important differences between SC and IV administration. Although initial outpatient IV treprostinil dosing was higher, SC titration was accelerated more aggressively and a higher dose was achieved by MOT3 suggesting that factors specific to SC administration (e.g., site pain) may not limit dosing and titration as previously thought.

Survival and drug persistence in patients receiving inhaled treprostinil at doses greater than 54 µg (nine breaths) four times daily

Treprostinil is a prostacyclin approved for the treatment of pulmonary arterial hypertension. Commercial data sets indicate that approximately 20-25% of patients are prescribed a higher dose than the maximum recommended dosage of nine breaths per treatment session (bps) (54 μg), four times a day (QID) and numerous studies have demonstrated the safety of doses >9 bps QID. This phase 4, retrospective analysis of specialty pharmacy records assessed the effects of inhaled treprostinil at doses >9 bps QID. Patients receiving inhaled treprostinil between September 2009 and June 2018 were included, and a random sampling of 5000 patients was selected for further analysis. Subjects were grouped based on the highest dose reached for ≥2 months within a rolling six-month window and were followed for up to three years. Of the total of 5000 patients analyzed, 28.5% received >9 bps QID. Survival rates were significantly higher in the >9 bps QID dosing group for years one, two, and three (P < 0.001). The time to transition to parenteral therapy was significantly longer for those at doses >9 bps (17.5 months) compared to doses ≤9 bps (9.5 moths; P < 0.0001). Drug persistence was also significantly higher for those taking >9 bps at years 1, 2, and 3 (P < 0.0001). Patients receiving inhaled treprostinil at doses >9 bps QID had a higher rate of survival and drug persistence over a three-year period, suggesting that higher doses may provide clinically relevant benefits while remaining tolerable.

Development of the Pulmonary Hypertension Functional Classification Self-Report: a patient version adapted from the World Health Organization Functional Classification measure

Background

Pulmonary arterial hypertension (PAH) is characterized by progressive limitations on physical activity, right heart failure, and premature death. The World Health Organization functional classification (WHO-FC) is a clinician-rated assessment used widely to assess PAH severity and functioning, but no equivalent patient-reported version of PAH symptoms and activity limitations exists. We developed a version of the WHO-FC for self-completion by patients: the Pulmonary Hypertension Functional Classification Self-Report (PH-FC-SR).

Methods

Semistructured interviews were conducted with three health care providers (HCPs) via telephone to inform development of the draft PH-FC-SR. Two rounds of semi-structured interviews were conducted with 14 US patients with a self-reported PAH diagnosis via telephone/online to elicit concepts and iteratively refine the PH-FC-SR.

Results

HCPs reported that the WHO-FC was a useful tool for evaluating patients’ PAH severity over time and for making treatment decisions but acknowledged that use of the measure is subjective. Patients in round 1 interviews (n = 6) reported PAH symptoms, including shortness of breath (n = 6), fatigue (n = 5), syncope (n = 5), chest pains (n = 3), and dizziness (n = 3). Round 1 patients identified challenges with the original WHO-FC, including comprehensibility of clinical terms and overlapping descriptions of class II and III, and preferred the Draft 1 PH-FC-SR over the original WHO-FC. After minor changes were made to Draft 2, round 2 interviews (n = 8) confirmed patients understood the PH-FC-SR class descriptions, interpreting them consistently.

Conclusions

The HCP and patient interviews identified and confirmed certain limitations inherent within the clinician-rated WHO-FC, including subjective assessment and overlapping definitions for class II and III. The PH-FC-SR includes patient-appropriate language, symptoms, and physical activity impacts relevant to patients with PAH. Future research is recommended to validate the PH-FC-SR and explore its correlation with the physician-assessed WHO-FC and other outcomes.

Pulmonary hypertension due to interstitial lung disease or chronic obstructive pulmonary disease: a patient experience study of symptoms and their impact on quality of life

Pulmonary hypertension resulting from chronic lung disease such as chronic obstructive pulmonary disease and interstitial lung disease is categorized by the World Health Organization as Group 3 pulmonary hypertension. To identify the symptoms and impacts of World Health Organization Group 3 pulmonary hypertension and to capture data related to the patient experience of this disease, qualitative research interviews were undertaken with 3 clinical experts and 14 individuals with pulmonary hypertension secondary to chronic obstructive pulmonary disease or interstitial lung disease. Shortness of breath, fatigue, cough, and swelling were the most frequently reported symptoms of pulmonary hypertension due to chronic obstructive pulmonary disease or interstitial lung disease, and shortness of breath was further identified as the single most bothersome symptom for most patients (71.4%). Interview participants also described experiencing a number of impacts related to pulmonary hypertension and pulmonary hypertension symptoms, including limitations in the ability to perform activities of daily living and impacts on physical functioning, family life, and social life as well as emotional impacts, which included frustration, depression, anxiety, isolation, and sadness. Results of these qualitative interviews offer an understanding of the patient experience of pulmonary hypertension due to chronic obstructive pulmonary disease or interstitial lung disease, including insight into the symptoms and impacts that are most important to patients in this population. As such, these results may help guide priorities in clinical treatment and assist researchers in their selection of patient-reported outcome measures for clinical trials in patients with pulmonary hypertension due to chronic obstructive pulmonary disease or interstitial lung disease.

Impact of inhaled treprostinil on risk stratification with noninvasive parameters: a post hoc analysis of the TRIUMPH and BEAT studies

The 2015 European Society of Cardiology/European Respiratory Society treatment guidelines recommend frequent risk assessment in pulmonary arterial hypertension utilizing risk variables. Our objectives were: (1) to investigate the impact of inhaled treprostinil on risk stratification using the French noninvasive approach and REVEAL 2.0, and (2) to analyze the prognostic utility of both risk stratification methods in the predominantly New York Heart Association/World Health Organization functional class III/IV cohorts of TRIUMPH and BEAT. A post hoc analysis was performed to assess risk at baseline and follow-up at Week 12 in the TRIUMPH cohort (n = 148) and at Week 16, 21, and 30 in the inhaled treprostinil naïve placebo BEAT cohort (n = 73). Overall survival, clinical worsening-free survival, and pulmonary arterial hypertension-related hospitalization-free survival were all assessed in the pooled TRIUMPH and inhaled treprostinil naïve placebo BEAT cohorts based on risk group/strata at Week 12/16 follow-up. Inhaled treprostinil improved REVEAL 2.0 risk stratum (OR: 2.38, 95% CI: 1.09–5.19, p = 0.0298) and REVEAL 2.0 score (p = 0.0008) compared to placebo in the TRIUMPH cohort at Week 12. REVEAL 2.0 risk stratum and the number of low-risk criteria by the French approach improved at Weeks 16, 21, and 30 in the inhaled treprostinil naïve placebo BEAT cohort. Combining cohorts, REVEAL 2.0 risk stratification at follow-up was prognostic for clinical worsening-free, pulmonary arterial hypertension hospitalization-free, and overall survival, whereas the number of low-risk criteria was not. These post-hoc pooled analyses suggest inhaled treprostinil improves risk status and indicates that the REVEAL 2.0 calculator may be more suitable than the French noninvasive method for evaluating short-term clinical change in the New York Heart Association/World Health Organization functional class III/IV population.

Implantable system for treprostinil: a real-world patient experience study

Parenteral prostanoids are effective for improving outcomes in patients with pulmonary arterial hypertension. However, subcutaneous or intravenous delivery via an external pump places a significant burden on patients. Consequently, the Implantable System for Remodulin© (treprostinil) was developed and is associated with a low rate of complications (United Therapeutics (Research Triangle Park, NC) in collaboration with Medtronic, Inc. (Mounds View, MN)). The current real-world experience study evaluated pulmonary arterial hypertension patients' perceptions of their quality of life, ability to perform activities of daily living, perceptions on the benefits and risks of the implantable system, and their social interactions before and after receiving the implantable system. Pulmonary arterial hypertension patients who had been transitioned from an external infusion pump to the implantable system completed a mix of quantitative and qualitative questions administered online over the course of a six-day period. A total of 20 patients completed the study. All patients reported that their quality of life, confidence out in public, and ability to travel long distances had improved. Over 90% of patients reported that their overall level of independence was better since receiving the implantable system, and most patients indicated that their ability to independently perform specific activities of daily living had improved. Responses to the qualitative questions suggested that the implantable system saved time, improved interpersonal relationships, and increased freedom. Results from this real-world patient experience study suggest this novel delivery system provides improvements in factors that are of substantial importance to patients.

Bronchodilation induced by PGE2 is impaired in Group III pulmonary hypertension

BACKGROUND AND PURPOSE

In patients with pulmonary hypertension (PH) associated with lung disease and/or hypoxia (Group III), decreased pulmonary vascular tone and tissue hypoxia is therapeutically beneficial. PGE₂ and PGI₂ induce potent relaxation of human bronchi from non-PH (control) patients via EP₄ and IP receptors, respectively. However, the effects of PGE₂ /PGI₂ and their mimetics on human bronchi from PH patients are unknown. Here, we have compared relaxant effects of several PGI₂ -mimetics approved for treating PH Group I with several PGE₂ -mimetics, in bronchial preparations derived from PH Group III and control patients.

EXPERIMENTAL APPROACH

Relaxation of bronchial muscle was assessed in samples isolated from control and PH Group III patients. Expression of prostanoid receptors was analysed by western blot and real-time PCR, and endogenous PGE₂ , PGI₂ , and cAMP levels were determined by ELISA.

KEY RESULTS

Maximal relaxations induced by different EP₄ receptor agonists (PGE₂ , L-902688, and ONO-AE1-329) were decreased in human bronchi from PH patients, compared with controls. However, maximal relaxations produced by PGI₂ -mimetics (iloprost, treprostinil, and beraprost) were similar for both groups of patients. Both EP₄ and IP receptor protein and mRNA expressions were significantly lower in human bronchi from PH patients. cAMP levels significantly correlated with PGI₂ but not with PGE₂ levels.

CONCLUSION AND IMPLICATIONS

The PGI₂ -mimetics retained maximal bronchodilation in PH Group III patients, whereas bronchodilation induced by EP₄ receptor agonists was decreased. Restoration of EP₄ receptor expression in airways of PH Group III patients with respiratory diseases could bring additional therapeutic benefit.

Dosing characteristics of oral treprostinil in real-world clinical practice

Pharmacokinetic studies with oral treprostinil demonstrate that three times daily (TID) dosing reduces peak-to-trough plasma trepostinil fluctuations compared with twice daily (BID) dosing. TID dosing may allow for faster titration, higher total daily doses, and potentially improve the tolerability of oral trepostinil. This analysis, which looks at the real-world dosing of oral treprostinil, supports the utility of TID dosing.

Rapid transition from inhaled iloprost to inhaled treprostinil in patients with pulmonary arterial hypertension

Background

Inhaled treprostinil is a prostacyclin analog approved for the treatment of pulmonary arterial hypertension (PAH) that may provide a more convenient treatment option for patients receiving inhaled iloprost while maintaining the clinical benefit of inhaled prostacyclin therapy.

Aims

In this open-label safety study, 73 PAH patients were enrolled with primarily World Health Organization Class II (56%) or III (42%) symptoms. At baseline, most patients (93%) were receiving 5 μg of iloprost per dose but 38% of patients reported a dosing frequency below the labeled rate of 6–9 times daily. Patients initiated inhaled treprostinil at 3 breaths four times daily (qid) at the immediate next scheduled iloprost dose. The primary objective was to assess the safety of rapid transition from iloprost to inhaled treprostinil; clinical status and quality of life were also assessed.

Results

Most patients (84%) achieved the target treprostinil dose of 9 breaths qid and remained on study until transition to commercial therapy (89%). The most frequent adverse events (AEs) were cough (74%), headache (44%), and nausea (30%), and five patients prematurely discontinued study drug due to AE (n = 3), disease progression (n = 1), or death (n = 1). At week 12, the time spent on daily treatment activities was reduced compared to baseline, with a mean total savings of 1.4 h per day. Improvements were also observed at week 12 for 6-min walk distance (+16.0; P < 0.001), N-terminal pro-B-type natriuretic peptide (−74 pg/mL; P = 0.001), and the Cambridge Pulmonary Hypertension Outcome Review (all domains P < 0.001).

Conclusions

Pulmonary arterial hypertension patients can be safely transitioned from inhaled iloprost to inhaled treprostinil while maintaining clinical status.

Treatment satisfaction is associated with improved quality of life in patients treated with inhaled treprostinil for pulmonary arterial hypertension

Background

Patient treatment satisfaction is likely to be a highly relevant outcome measure in pulmonary arterial hypertension (PAH), a condition for which the benefits of treatment must be weighed against frequent, undesirable side effects, inconvenience, and complications associated with therapy. In this study, we sought to evaluate the psychometric properties of a patient-reported treatment satisfaction measure and its relationship to quality of life (QoL) among patients transitioning from inhaled iloprost (iILO) to inhaled treprostinil (iTRE).

Methods

We studied treatment satisfaction among 66 subjects with PAH in a single-arm, open-label, multi-center trial of iTRE following transition from iILO. Treatment satisfaction was assessed using the Treatment Satisfaction Questionnaire for Medication (TSQM, version 1.4) administered to subjects immediately before and 12 weeks after transition of inhaled therapy. The TSQM is comprised of 4 domains: effectiveness, side effects, convenience, and global satisfaction. Scores range from 0 to 100 with higher scores indicating greater satisfaction. Six-minute walk distance (6MWD), functional class, adverse events, drug administration time, and PAH-specific QoL (CAMPHOR) were concurrently assessed.

Results

Domains of the TSQM demonstrated evidence of strong internal consistency at baseline and at 12 weeks (Cronbach α = 0.88-0.93). Transition from iILO to iTRE was associated with an improvement in 3 of 4 TSQM domains: effectiveness (+20 ± 21, p < 0.0001), side effects (0 ± 22, p = 0.97), convenience (+39 ± 26, p < 0.0001), and global satisfaction (+20 ± 24, p = 0.0005). Change in effectiveness scores correlated with change in 6MWD (r = 0.43, p = 0.0004) and side effects scores at 12 weeks correlated inversely with number of severity-weighted treatment-emergent adverse events (r = −0.44, p = 0.0002). In multiple regression models adjusted for baseline characteristics, changes in effectiveness and convenience satisfaction scores were significantly associated with improvement in PAH-specific QoL (p = 0.002 and p = 0.01).

Conclusions

The TSQM demonstrated acceptable performance characteristics in patients with PAH. Changes in treatment satisfaction resulting from transitioning from iILO to iTRE were associated with improvements in PAH-specific QoL.

Consistency of Response to Sumatriptan/Naproxen Sodium in a Placebo-Controlled, Crossover Study

Two identical randomized, placebo-controlled, crossover studies were conducted to evaluate consistency of response to sumatriptan/naproxen sodium 85/500 mg (S/NS) over four attacks in adults with migraine. Patients were instructed to treat within 1 h of pain onset while pain was mild. Co-primary end-points were pain-free response at 2 h (2hPF) and 24-h sustained pain-free response (24hSPF) calculated as percentages of all attacks. In Study 1, 570 patients treated 1693 attacks with S/NS and 424 with placebo. In Study 2, 565 patients treated 1678 attacks with S/NS and 422 with placebo. Compared with placebo, S/NS conferred higher 2hPF rates (Study 1: S/NS 52%, placebo 25%; Study 2: S/NS 50%, placebo 20%; both P < 0.001) and higher 24hSPF rates (Study 1: S/NS 37%, placebo 17%; Study 2: S/NS 34%, placebo 12%; both P < 0.001). 2hPF was reported in at least two of the first three S/NS-treated attacks in 55.0% of patients in Study 1 and 52.1% of patients in Study 2. 24hSPF was reported in at least two of the first three S/NS-treated attacks in 35.7% of patients in Study 1 and 32.6% of patients in Study 2. The incidences of any adverse event and of specific adverse events were low and generally similar between S/NS and placebo.

Medullary pain facilitating neurons mediate allodynia in headache-related pain

OBJECTIVE

To develop and validate a model of cutaneous allodynia triggered by dural inflammation for pain associated with headaches. To explore neural mechanisms underlying cephalic and extracephalic allodynia.

METHODS

Inflammatory mediators (IM) were applied to the dura of unanesthetized rats via previously implanted cannulas, and sensory thresholds of the face and hind-paws were characterized.

RESULTS

IM elicited robust facial and hind-paw allodynia, which peaked within 3 hours. These effects were reminiscent of cutaneous allodynia seen in patients with migraine or other primary headache conditions, and were reversed by agents used clinically in the treatment of migraine, including sumatriptan, naproxen, and a calcitonin gene-related peptide antagonist. Consistent with clinical observations, the allodynia was unaffected by a neurokinin-1 antagonist. Having established facial and hind-paw allodynia as a useful animal surrogate of headache-associated allodynia, we next showed that blocking pain-facilitating processes in the rostral ventromedial medulla (RVM) interfered with its expression. Bupivacaine, destruction of putative pain-facilitating neurons, or block of cholecystokinin receptors prevented or significantly attenuated IM-induced allodynia. Electrophysiological studies confirmed activation of pain-facilitating RVM "on" cells and transient suppression of RVM "off" cells after IM.

INTERPRETATION

Facial and hind-paw allodynia associated with dural stimulation is a useful surrogate of pain associated with primary headache including migraine and may be exploited mechanistically for development of novel therapeutic strategies for headache pain. The data also demonstrate the requirement for activation of descending facilitation from the RVM for the expression of cranial and extracranial cutaneous allodynia, and are consistent with a brainstem generator of allodynia associated with headache disorders.

Treatment satisfaction and efficacy of the rapid release formulation of sumatriptan 100 mg tablets utilising an early intervention paradigm in patients previously unsatisfied with sumatriptan

AIMS

To evaluate treatment satisfaction, efficacy and functional ability of the rapid release formulation of sumatriptan 100 mg tablets (sumatriptan RT 100 mg) in an early intervention paradigm in patients who were dissatisfied with low-dose sumatriptan and not completely satisfied with their current migraine regimen.

METHODS

Experienced migraineurs who reported a mild migraine pain phase, dissatisfaction with the previous sumatriptan treatment and some dissatisfaction with their current treatment regimen had no experience with sumatriptan at the 100 mg dose were enrolled in an open-label, single group study. Subjects were instructed to treat four migraine attacks within 30 min of the onset of mild pain. Treatment satisfaction was measured with the Patient Perception of Migraine Questionnaire Revised version (PPMQ-R) questionnaire.

RESULTS

More than half of the subjects were either very satisfied or satisfied with the efficacy of early intervention sumatriptan RT 100 mg after each attack and at the follow-up study visit. The mean total PPMQ-R score was 75.2 out of 100. Between 63% and 73% of subjects were pain-free within 4 h of dosing. Between 79% and 90% of subjects reported an ability to function normally within 4 h of taking the study medication.

CONCLUSION

Subjects who were previously unsatisfied with lower doses of sumatriptan and less than very satisfied with their current treatment regimen were more likely to be satisfied or very satisfied with sumatriptan RT 100 mg in an early intervention paradigm. Results were consistent across four migraine attacks and at a follow-up visit. The treatment satisfaction results corresponded with positive results on efficacy measures and a functional status measure.

The influence of CYP3A5 genotype on dexamethasone induction of CYP3A activity in African Americans

The CYP3A5(*)1 allele has been associated with differences in the metabolism of some CYP3A substrates. CYP3A5 polymorphism may also influence susceptibility for certain drug interactions. We have previously noted a correlation between basal CYP3A activity and the inductive effects of dexamethasone using the erythromycin breath test (ERBT). To determine whether CYP3A5 polymorphism influences induction of CYP3A activity, we examined the effect of an antiemetic regimen of dexamethasone, and the prototypical inducer rifampin, on the ERBT in African American volunteers prospectively stratified by CYP3A5(*)1 allele carrier status. Mean basal ERBTs were significantly higher in CYP3A5(*)1 carriers (2.71 +/- 0.53%) versus noncarriers (2.12 +/- 0.37%, P = 0.006). Rifampin increased ERBTs in CYP3A5(*)1 carriers (4.68 versus 2.60%, P = 0.0008) and noncarriers (3.55 versus 2.11%, P = 0.0017), whereas dexamethasone increased ERBTs only in CYP3A5(*)1 noncarriers (3.03 versus 2.14%, P = 0.031). CYP3A5 polymorphism appears to influence susceptibility to induction-type drug interactions for some inducers, and CYP3A5(*)1 noncarriers may be more susceptible to the inductive effects of dexamethasone as a result of lower basal CYP3A activity.

Enhanced aqueous dissolution of a poorly water soluble drug by novel particle engineering technology: spray-freezing into liquid with atmospheric freeze-drying

PURPOSE

The purpose of this work was to investigate spray-freezing into liquid (SFL) and atmospheric freeze-drying (ATMFD) as industrial processes for producing micronized SFL powders with enhanced aqueous dissolution. Micronized SFL powders dried by ATMFD were compared with vacuum freeze-dried SFL powders.

METHOD

Danazol was formulated with polyvinyl alcohol (MW 22,000), polyvinylpyrrolidone K-15, and poloxamer 407 to produce micronized SFL powders that were freeze-dried under vacuum or dried by ATMFD. The powders were characterized using Karl-Fischer titration, gas chromatography, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, surface area, and dissolution testing (SLS 0.75%/Tris 1.21% buffer media).

RESULTS

Micronized SFL powders containing amorphous drug were successfully dried using the ATMFD process. Micronized SFL powders contained less than 5% w/w and 50 ppm of residual water and organic solvent, respectively, which were similar to those contents detected in a co-ground physical mixture of similar composition. Micronized SFL powders dried by ATMFD had lower surface areas than powders produced by vacuum freeze-drying (5.7 vs. 8.9 m2/g) but significantly greater surface areas than the micronized bulk drug (0.5 m2/g) and co-ground physical mixture (1.9 m2/g). Rapid wetting and dissolution occurred when the SFL powders were introduced into the dissolution media. By 5 min, 100% dissolution of danazol from the ATMFD-micronized SFL powder had occurred, which was similar to the dissolution profile of the vacuum freeze-dried SFL powder.

CONCLUSIONS

Vacuum freeze-drying is not a preferred technique in the pharmaceutical industry because of scalability and high-cost concerns. The ATMFD process enables commercialization of the SFL particle-engineering technology as a micronization method to enhance dissolution of hydrophobic drugs.

A novel particle engineering technology to enhance dissolution of poorly water soluble drugs: spray-freezing into liquid

A novel cryogenic spray-freezing into liquid (SFL) process was developed to produce microparticulate powders consisting of an active pharmaceutical ingredient (API) molecularly embedded within a pharmaceutical excipient matrix. In the SFL process, a feed solution containing the API was atomized beneath the surface of a cryogenic liquid such that the liquid-liquid impingement between the feed and cryogenic liquids resulted in intense atomization into microdroplets, which were frozen instantaneously into microparticles. The SFL micronized powder was obtained following lyophilization of the frozen microparticles. The objective of this study was to develop a particle engineering technology to produce micronized powders of the hydrophobic drug, danazol, complexed with hydroxypropyl-beta-cyclodextrin (HPbetaCD) and to compare these SFL micronized powders to inclusion complex powders produced from other techniques, such as co-grinding of dry powder mixtures and lyophilization of bulk solutions. Danazol and HPbetaCD were dissolved in a water/tetrahydrofuran cosolvent mixture prior to SFL processing or slow freezing. Identical quantities of the API and HPbetaCD used in the solutions were co-ground in a mortar and pestle and blended to produce a co-ground physical mixture for comparison. The powder samples were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy, surface area analysis, and dissolution testing. The results provided by DSC, XRD, and FTIR suggested the formation of inclusion complexes by both slow-freezing and SFL. However, the specific surface area was significantly higher for the latter. Dissolution results suggested that equilibration of the danazol/HPbetaCD solution prior to SFL processing was required to produce the most soluble conformation of the resulting inclusion complex following SFL. SFL micronized powders exhibited better dissolution profiles than the slowly frozen aggregate powder. Results indicated that micronized SFL inclusion complex powders dissolved faster in aqueous dissolution media than inclusion complexes formed by conventional techniques due to higher surface areas and stabilized inclusion complexes obtained by ultra-rapid freezing.

A medical resident in Ponape

The University of Hawaii has an elective two-month primary care rotation in Ponape, in the Eastern Caroline Islands, for senior medical residents. Many diagnostic and therapeutic situations provide unusual challenges because of the tropical environment and the paucity of medical facilities. Parasitoses, tuberculosis and trauma are common, and certain diseases, such as cholelithiasis and coronary artery disease, have a low incidence, reflecting the socio-economic conditions. The local intoxicant, sakau, seems to be responsible for dermatologic, pulmonary, and possibly hepatic and neurologic disorders. The rotation has proved to be a worthwhile educational experience for residents and a benefit to the people of Ponape.