Significant differences on submission lag following regulation reform for registration of novel therapeutic drugs in Taiwan.

Drug lag, which delays patients' access to medicinal products, is typically associated with pharmaceutical regulations. To shorten drug lag, health authorities may establish new policies to liberalize the regulations, a step that is important in countries, such as Taiwan, with consumer demand for imported novel therapeutic agents. Taiwan's government enacted Articles 38-1 and 38-2 of Regulations for Registration of Medicinal Products to relax the regulatory barriers for new drug submission, thus conditionally exempting the requirement for the Certificate of Pharmaceutical Product (CPP). This study examined whether the enacted regulations reduce submission lag by analyzing the time gap of submission between Taiwan and the United States during 2014-2017. The results indicated that the enacted regulations substantially affected submission lag. Submission lag was significantly shorter for applications not requiring a CPP than those requiring one CPP, which in turn was significantly shorter than those requiring two CPPs. This conclusion can be applied to biological, chemical, non-orphan, and oncology drugs and also applications filed by subsidiary companies, but not orphan drugs and applications filed by contract agents. Among applications requiring one CPP, oncology drugs showed the shortest submission lag. Certain factors, such as clinical studies recruiting over-threshold Taiwanese participants and those performed before the submission of new drug application in the United States, may shorten submission lag. In summary, this study justifies the policy of the exemption from CPP requirements, which supports the hypothesis that relaxing regulatory barriers can reduce submission lag in Taiwan.

Analysis of refuse-to-file policy for generic drug application in Taiwan.

Generic drugs are accounted for majority of medicinal products. To reduce the unnecessary review for incomplete dossiers of generic drugs, Taiwanese government launched a refuse-to-file (RTF) process since 2017. The present study aimed to examine the outcome of RTF process by analyzing application characteristic, RTF rate and deficiencies found in the submitted dossiers. Descriptive analyses of administrative information, chemistry, manufacturing and controls, bioequivalence study, and comparative dissolution testing were presented during the first 6 months after the implementation of RTF policy. The results showed that the source of application was likely a determinant to the RTF outcome, i.e., foreign rather than domestic applications were more liable to be RTF. It is possibly that (i) RTF applications were mainly due to incomplete dossiers regarding bioequivalence study and comparative dissolution testing, and (ii) the studies (bioequivalence and dissolution) of domestic applications conducted locally are exempted from the RTF process because they are allowed to submit for review before generic drug applications. Finally, the dossier integrity appeared not improved during the period of analysis as the number of RTF did not reduce by month. Results of the present study may help pharmaceutical industry to improve the dossiers' quality by fixing the deficiencies of generic drug submission.

Advantages of using an abbreviated dossier for drug master file applications in Taiwan.

In Taiwan, the quality of active pharmaceutical ingredients is recorded in a drug master file (DMF), the applications for which can be submitted in two dossier types, either full (complete technical information) or abbreviated (partially complete technical information with an approved document issued by developed countries). However, the advantages of the abbreviated approach remain unknown. This study compared full and abbreviated dossier profiles and reviewed their outcomes in acceptance rates and deficiencies leading to rejection. Data were collected from new submissions of both dossier types that were completed in 2014 by the Center for Drug Evaluation, Taiwan. The results revealed that the abbreviated applications took shorter review time and had a higher acceptance rate. Among the eligible types of document for abbreviated applications, Certification of Suitability to the Monographs of the European Pharmacopeia (CEP) was the most frequently used. For categorical deficiencies, both dossier types presented the deficiencies in similar sections leading to rejection, namely Manufacture (3.2.S.2), Control of drug substance (3.2.S.4), and Stability (3.2.S.7). In summary, CEP serves a favorable document for the abbreviated DMF application in which it shortens the review time, increases the acceptance rate, and its deficiencies are similar to those of the full DMF application.

Effect of regulation reform on clinical trials for registering novel therapeutic agents in Taiwan: a chronological analysis.

The registration process for new drugs is crucial in the clinical application of medicines. Previously, the registration of imported novel therapeutic agents in Taiwan depended considerably on their approvals in developed countries. The Taiwanese government enacted Article 38-1 of the Regulations for Registration of Medicinal Products in September 2009. According to the new submission criteria, approvals may be exempted if the number of Taiwanese participants in the clinical trials fulfills the required threshold. The present study compared the profiles of clinical trials of novel therapeutic agents before and after the enactment of this regulation in terms of over-threshold trials, structural types, and therapeutic areas across phases. The outcome-whether the liberalization of the submission criteria functioned as an incentive to launch clinical trials in Taiwan-was also evaluated. The results revealed that the number of clinical trial applications increased after the reformed regulation was enacted, even after the over-threshold criteria were considered; however, the increase disappeared for phase III trials. Most clinical trials were for chemical products and antineoplastic agents across all phases and study periods before and after the enactment of Article 38-1. Furthermore, the increase in the number of international clinical trials conducted in Taiwan was not directly caused by the regulation reform because the percentage of investigational products fulfilling the exemption criteria did not increase. These paradoxical results were interpreted in several aspects, referring particularly to the well-established infrastructure for launching clinical trials as well as the integral environment of medical services in Taiwan.

Helicobacter pylori stool antigen test in patients with bleeding peptic ulcers.

BACKGROUND: Helicobacter pylori has been linked to chronic gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Invasive tests are less sensitive than noninvasive tests in diagnosing H. pylori infection in patients with bleeding peptic ulcers. The H. pylori stool antigen test has been useful in diagnosing H. pylori in patients with peptic ulcers before and after eradication of H. pylori. The aim of this study was to evaluate the H. pylori stool antigen test in patients with bleeding peptic ulcers. METHODS: Patients with bleeding and nonbleeding peptic ulcers underwent a rapid urease test, histology, bacterial culture and H. pylori stool antigen test. Positive H. pylori infection was defined as a positive culture or both a positive histology and a positive rapid urease test. Helicobacter pylori stool antigen was assessed with a commercial kit (Diagnostec H. pylori antigen EIA Kit, Hong Kong). RESULTS: Between October 2000 and April 2002, 93 patients with bleeding peptic ulcers (men/women: 78/15, gastric ulcer/duodenal ulcer: 58/35) and 59 patients with nonbleeding peptic ulcers (men/women: 47/12, gastric ulcer/duodenal ulcer: 30/29) were enrolled in this study. Forty-seven (50.5%) patients with bleeding peptic ulcers and 30 (50.8%) patients with nonbleeding peptic ulcers, were found to be infected with H. pylori (p > .1). Helicobacter pylori stool antigen tests were positive in 54 (58.1%) and 30 (50.8%) patients with bleeding peptic ulcers and nonbleeding peptic ulcers, respectively (p > .1). The sensitivity (82% vs. 93%), specificity (68% vs. 93%), positive predictive value (74% vs. 93%), negative predictive value (77% vs. 93%) and diagnostic accuracy (75% vs. 93%) were all lower in patients with bleeding vs. nonbleeding peptic ulcers. The specificity, positive predictive value, and diagnostic accuracy of the H. pylori stool antigen test in patients with bleeding peptic ulcers were significantly lower than those in patients with nonbleeding peptic ulcers (p = .01, p = .02 and p = .003, respectively). CONCLUSION: The H. pylori stool antigen test is not reliable for diagnosing H. pylori infection in patients with bleeding peptic ulcers.

Helicobacter pylori cagA, iceA and vacA genotypes in patients with gastric cancer in Taiwan.

AIM: Helicobacter pylori (H pylori ) has been linked to chronic gastritis, peptic ulcer, gastric cancer and MALT-lymphoma. The link of genotypes of H pylori to gastric cancer remains controversial. The aim of this study was to investigate the H pylori vacA alleles, cagA and iceA in patients with gastric cancer in Taiwan. METHODS: Patients with gastric cancer, peptic ulcer and chronic gastritis were enrolled in this study. We obtained biopsy specimens from the stomach at least 2 cm away from the tumor margin in patients with gastric cancer, and from the antrum of stomach in patients with peptic ulcer or chronic gastritis. DNA extraction and polymerase chain reaction were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 168 patients (gastric ulcer: 77, duodenal ulcer: 66, and chronic gastritis: 25) were found to have positive PCR results of the biopsy specimens from patients with peptic ulcer and chronic gastritis. We found positive cagA (139/168, 83%), m2 (84/168, 50%) and iceA1 (125/168, 74%) strains in the majority of patients. In patients with gastric cancer, the vacA s1a and s1c subtypes were less commonly found than those in non-cancer patients (35/66 vs 127/168, P = 0.0001 for s1a and 13/66 vs 93/168, P<0.0001 for s1c). In the middle region, the m1T strain in patients with gastric cancer was more than that of non-cancer patients (23/66 vs 33/168, P = 0.02). CONCLUSION: In Taiwan, H pylori with positive vacA s1a, cagA and iceA1 strains are found in the majority of patients with gastric cancer or non-cancer patients. In patients with gastric cancer, the vacA s1a and s1c subtypes are less and m1T is more than in patients with peptic ulcer and chronic gastritis.

Genotypes of Helicobacter pylori in patients with peptic ulcer bleeding.

AIM: Helicobacter pylori causes chronic gastritis, peptic ulcer, gastric cancer and MALT-lymphoma. Different genotypes of Helicobacter pylori are confirmed from diverse geographic areas. Its association with bleeding peptic ulcer remains controversial. The aim of this study was to investigate the Helicobacter pylori vacA alleles, cagA and iceA in patients with bleeding peptic ulcer. METHODS: We enrolled patients with bleeding, non-bleeding peptic ulcers and chronic gastritis. Biopsy specimens were obtained from the antrum of the stomach for rapid urease test, bacterial culture and PCR assay. DNA extraction and polymerase chain reaction were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 168 patients (60.4%) (25 patients with chronic gastritis, 26 patients with bleeding gastric ulcer, 51 patients with non-bleeding gastric ulcer, 26 patients with bleeding duodenal ulcer, and 40 patients with non-bleeding duodenal ulcer) were found to have positive PCR results between January 2001 and December 2002. Concerning genotypes, we found cagA (139/278, 50%), vacA s1a (127/278, 45.7%), and ice A1 (125/278, 45%) predominated in all studied patients. In patients with bleeding peptic ulcers, vacA s1a and m1T were fewer than those in patients with non-bleeding peptic ulcers (37/106 vs 69/135, P=0.017, and 4/106 vs 21/135, P =0.002). CONCLUSION: In patients with peptic ulcers, H pylori vacA s1a and m1T prevent bleeding complication.

Helicobacter pylori cagA, iceA and vacA status in Taiwanese patients with peptic ulcer and gastritis.

BACKGROUND: Helicobacter pylori causes chronic gastritis, peptic ulcer, gastric cancer and mucosa-associated lymphoid tissue (MALT) lymphoma. Different genotypes of H. pylori are confirmed from diverse geographical areas. Its association with clinical diseases remains controversial. The aim of the present study was to investigate the H. pylori vacuolating cytotoxin (vacA) alleles, cytotoxin-associated gene (cagA) and iceA, in patients with peptic ulcer and gastritis. METHODS: We enrolled patients with peptic ulcer and chronic gastritis. Biopsy specimens were obtained from the antrum and lower body of the stomach. DNA extraction and polymerase chain reaction (PCR) were used to detect the presence or absence of cagA and to assess the polymorphism of vacA and iceA. RESULTS: A total of 133 patients (57 gastric ulcer, 52 duodenal ulcer, 24 chronic gastritis) had positive PCR results from biopsy specimens. Concerning genotypes, we found cagA (79% in the antrum, 92% in the body) and iceA1 (73% in the antrum, 82.8% in the body) strains in the majority of patients. The dominant vacA subtype was s1a (74.4% in the antrum, 75% in the body), followed by s1c (51.1% in the antrum, 60.5% in the body). In the middle region, the m2 strain dominated (49.6% in the antrum, 41.4% in the body), followed by m1T (19.5% in the antrum, 9.5% in the body). Mixed infection occurred in 89 patients (67%). There was no statistical difference in genotypes among the three groups. CONCLUSION: In Taiwan, H. pylori with positive cagA and iceA1 was found in the majority of cases. H. pylori with vacA s1a strains was the most common vacA subtype, followed by s1c, while s1b was rare. In the middle region, the m2 subtype was predominant followed by m1T. There was no significant association between genotypes and clinical diseases.

Plant-derived terpenoids and analogues as anti-HIV agents.

The plant-derived terpenoids and analogues are reviewed with respect to their anti-HIV activity, structure-activity relationships, and mechanism of action. The active compounds include diterpenoid lactones, phenolic diterpenes, atisane and kaurane diterpenes, phorbol diterpenes, triterpene glycosides, friedelane triterpenes, taraxerane triterpenes, ursane triterpenes, lanostane triterpene, lupane triterpenes, seco-ring A triterpenes, degraded triterpenes, and cucurbitacin triterpenes. Positive new leads for drug development will be highlighted.

Anti-AIDS agents 49. Synthesis, anti-HIV, and anti-fusion activities of IC9564 analogues based on betulinic acid.

The betulinic acid derivative IC9564 inhibits human immunodeficiency virus (HIV)-1 entry. Among a series of IC9564 derivatives, 5 and 20 were the most promising compounds against HIV infection with EC(50) values of 0.33 and 0.46 microM, respectively. Both compounds inhibited syncytium formation with EC(50) values of 0.40 and 0.33 microM, respectively. The comparable EC(50) values in the two assays suggested that these compounds are fusion inhibitors. The structure-activity relationship data also indicated that a double bond in IC9564 can be eliminated and the statine moiety can be replaced with L-leucine while retaining anti-HIV activity.