A practical reference on Phase 3 trial: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-05-10. Anything still debated is marked as such rather than presented as settled.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone family and contains the same forty-four amino acid sequence as endogenous GHRH, extended at the amino terminus by a trans-3-hexenoyl group. That small fatty acid modification protects the peptide from rapid cleavage by dipeptidyl peptidase-4, the enzyme that shortens the half-life of native GHRH to only a few minutes. Chemically the compound is produced by solid-phase peptide synthesis, purified by chromatography, and supplied as a sterile lyophilized powder for reconstitution.
Regulatory approval in the United States came in 2010, when the Food and Drug Administration cleared the peptide for the reduction of excess abdominal fat in adults with HIV infection and associated lipodystrophy. The decision rested mainly on two randomized phase 3 trials that enrolled roughly eight hundred patients and ran for twenty-six weeks. Participants receiving active drug showed substantially greater declines in visceral adipose tissue than those receiving placebo, while total body weight changed comparatively little. A reformulated presentation was later approved, and the product has remained a niche therapy rather than a general weight-loss agent.
冻干粉末一般在 -20°C 或更低温度、干燥避光条件下保存,可维持较长时间的稳定。复溶后稳定性明显下降,溶液中的肽链易发生水解、氧化与聚集,通常需冷藏并在短期内用完。反复冻融会加速聚集与降解,建议分装后单次使用。缓冲体系的 pH 与离子强度同样影响聚集速率,需要按具体实验条件验证。
研究用与临床用材料的标准并不相同。质量控制通常覆盖纯度、残留溶剂、反离子含量、微生物限度与内毒素水平,各项均有对应检测方法。随货文件应包含批号、检测项目、方法与结果,使数据可以追溯。核验时应关注纯度是否按主峰面积计算、杂质是否已定性、方法是否经过验证,这些信息决定结果能否被外部重复。
| Property | Value | Notes |
|---|---|---|
| Peptide class | Synthetic GHRH analogue | 44 residues; N-terminal trans-3-hexenoyl group |
| First approval year | 2010 | United States; HIV-associated abdominal fat accumulation |
| Administration route | Subcutaneous injection | Abdominal site; clinician-administered or self-injected |
| Common synonyms | TH9507; tesamorelin acetate | Development code and acetate salt form |
| Originator | Canadian biotechnology firm | Original developer and regulatory sponsor |
Several related peptides act on the same receptor, including sermorelin, a shorter GHRH fragment, and modified analogs such as CJC-1295 and modified GRF(1-29) that are common in research settings rather than approved products. Tesamorelin differs from growth hormone itself in that it acts upstream, prompting the pituitary to release the hormone through physiological signaling rather than supplying it directly. Terminology in the literature distinguishes GHRH analogs, growth hormone secretagogues, and recombinant growth hormone, although popular discussion often blurs these categories together. Precise naming matters when comparing study results.
Tesamorelin is a synthetic peptide of 44 amino acids that reproduces the sequence of human growth hormone-releasing hormone (GHRH) and carries a trans-3-hexenoyl group on its N-terminal tyrosine. That small fatty-acid modification blocks cleavage by dipeptidyl peptidase-4, the enzyme that rapidly degrades native GHRH in plasma. The result is a molecule with a longer circulating half-life than the natural hormone while retaining the same receptor target. It is supplied as a lyophilized powder for reconstitution and belongs to the broader class of GHRH analogs studied for effects on pituitary growth hormone secretion.
Development work on the compound, originally designated TH9507, focused on conditions in which reduced growth hormone signaling is thought to contribute to altered body composition. The United States Food and Drug Administration approved it in 2010 for the treatment of excess visceral abdominal fat in adults with human immunodeficiency virus infection and lipodystrophy. Later research examined other populations, including adults with mild cognitive impairment, where a large trial did not meet its primary endpoints. This mixed record illustrates how a single mechanism can produce clear effects in one setting and inconclusive results in another.
Measuring the effect of a growth hormone-releasing hormone analogue requires markers that reflect pituitary output rather than the peptide itself. The two most frequently used are growth hormone and insulin-like growth factor 1. Growth hormone fluctuates sharply across the day and responds to sleep, stress, and meals, so isolated readings can be difficult to interpret. Insulin-like growth factor 1 changes more slowly and is often treated as the more stable integrated marker of axis activity.
Because growth hormone is released in pulses, single measurements can misrepresent overall secretion. Investigators sometimes use repeated sampling or overnight profiles to capture the pattern rather than a single value. Provocative testing, in which a stimulus is given and the response is tracked over time, offers another way to characterize the axis. Each approach carries trade-offs between sensitivity, burden on the participant, and the influence of non-target variables.
Involuntarily, I compare the mummified sovereign—now small and weathered—to the giant man I saw in 1886 entering the See of São Paulo. Amidst a colossal wave of people, he dominated the crowd, appearing many cubits taller. The body of Pedro II and that of his wife Teresa Cristina (who was also embalmed) were officially repatriated to Brazil aboard a Brazilian Navy ship in 1921. The emperor and empress are now interred in the Imperial Mausoleum within the Cathedral of Saint Peter of Alcantara in Petrópolis, a city founded by Pedro II himself.
== Scoring == The LP-IR score ranges from 0 (most insulin-sensitive) to 100 (most insulin-resistant). It's calculated by weighting the six parameters, which are more strongly correlated with insulin resistance than individual lipid measures like triglycerides or HDL cholesterol alone. Results are typically categorized:
==== Other ==== People taking zinc supplements may slow down the progress to age-related macular degeneration. Zinc supplement is an effective treatment for acrodermatitis enteropathica, a genetic disorder affecting zinc absorption that was previously fatal to affected infants. Zinc deficiency has been associated with major depressive disorder (MDD), and zinc supplements may be an effective treatment. Zinc may help individuals sleep more.
==== Rivaroxaban ==== Rivaroxaban chemically belongs to the group of n-aryloxazolidinones. Other drugs of that group are linezolid and tedizolid, both of whom are antibiotics. A synthesis of n-aryloxazolidinones starting with an O-silyl protected ethyl(2,3-dihydroxypropyl)-carbamate was published in 2016. In a one-pot reaction the carbamate cyclisizes to a 2-oxazolidone ring under slightly basic conditions while simultaneously the oxazolidone nitrogen is arylized by copper-catalization. For rivaroxaban in particular, 3-morpholinone substitutes the iodine in p-position of the benzene ring by copper-catalization. Afterwards, the silyl protecting group is removed and the resulting alcohol is replaced by an amino group which is then acylated in the last step. An industrial preparation of rivaroxaban was registered as a patent by Bayer Healthcare in 2005. It starts from N-(4-aminophenol)-morpholinone which is alkylated by a propylene oxide derivate that also contains a primary amine involved in a phthalimide protection group. Next, a phosgene equivalent is added to form the 2-oxazolidone ring and the phthalimide is removed. The free amine can now be acylated which leads to rivaroxaban. However, according to the patent the synthesis has “various disadvantages in the reaction management which has particularly unfavourable effects for preparation“. The patent also explains another synthesis starting from a chlorothiophene derivate that would be more suitable for the industrial process but points out that toxic solvents or reagents have to be removed from the final product.
Sources: en.wikipedia.org
oxidation state Also oxidation number. 1. The degree of oxidation of an individual atom in a chemical compound, measured as the decrease in the number of electrons relative to the atom's naturally occurring elemental state. 2. The hypothetical electric charge (positive, negative, or zero) that an atom would have if all bonds to atoms of different elements were 100% ionic, with no covalent component.
A societal shift in the roles of women was significantly responsible for the large increase in female paid labor participation starting in the 1970s, and by 1985 the majority of American women aged 16 and older were employed. The Fall of Communism and the dissolution of the Soviet Union from 1989 to 1991 marked the end of the Cold War and left the United States as the world's sole superpower. This cemented the United States' global influence, reinforcing the concept of the "American Century" as the U.S. dominated international political, cultural, economic, and military affairs.
The concept of health technology assessment (HTA) was first coined in 1967 by the U.S. Congress in response to the increasing need to address the unintended and potential consequences of health technology, along with its prominent role in society. It was further institutionalized with the establishment of the congressional Office of Technology Assessment (OTA) in 1972–1973. HTA is defined as a comprehensive form of policy research that examines short- and long-term consequences of the application of technology, including benefits, costs, and risks. Due to the broad scope of technology assessment, it requires the participation of individuals besides scientists and health care practitioners such as managers and even the consumers. Several American organizations provide health technology assessments and these include the Centers for Medicare and Medicaid Services (CMS) and the Veterans Administration through its VA Technology Assessment Program (VATAP). The models adopted by these institutions vary, although they focus on whether a medical technology being offered is therapeutically relevant. A study conducted in 2007 noted that the assessments still did not use formal economic analyses. Aside from its development, however, assessment in the health technology industry has been viewed as sporadic and fragmented Issues such as the determination of products that needed to be developed, cost, and access, among others, also emerged.
The achievement of synthesizing ribonuclease A (with Bernd Gutte) was all the more significant in that it demonstrated that the linear sequence of amino acids joined in peptide bonds determined directly the protein tertiary structure, that is, information coded in one dimension can directly determine the three-dimensional structure of a molecule. SPPS has been expanded to include solid phase synthesis of nucleotides and saccharides.
Tyrannosaurus, like most dinosaurs, was long thought to have an ectothermic ("cold-blooded") reptilian metabolism. The idea of dinosaur ectothermy was challenged by scientists like Robert T. Bakker and John Ostrom in the early years of the "dinosaur renaissance", beginning in the late 1960s. T. rex itself was claimed to have been endothermic ("warm-blooded"), implying a very active lifestyle. Since then, several paleontologists have sought to determine the ability of Tyrannosaurus to regulate its body temperature. Histological evidence of high growth rates in young T. rex, comparable to those of mammals and birds, may support the hypothesis of a high metabolism. Growth curves indicate that, as in mammals and birds, T. rex growth was limited mostly to immature animals, rather than the indeterminate growth seen in most other vertebrates. Oxygen isotope ratios in fossilized bone are sometimes used to determine the temperature at which the bone was deposited, as the ratio between certain isotopes correlates with temperature. In one specimen, the isotope ratios in bones from different parts of the body indicated a temperature difference of no more than 4 to 5 °C (7 to 9 °F) between the vertebrae of the torso and the tibia of the lower leg. This small temperature range between the body core and the extremities was claimed by paleontologist Reese Barrick and geochemist William Showers to indicate that T. rex maintained a constant internal body temperature (homeothermy) and that it enjoyed a metabolism somewhere between ectothermic reptiles and endothermic mammals.
Sources: en.wikipedia.org
== Epidemiology == In the United States, the incidence of osteogenesis imperfecta is estimated to be one per 20,000 live births. An estimated 20,000 to 50,000 people are affected by OI in the United States. The most common types are I, II, III, and IV, while the rest are very rare. Type I is the most common and has been reported to be around three times more common than type II. The prevalence of types III and IV is less certain. In a 1989 study in Denmark, type I was found to comprise 71% of cases and type II 12% of cases, with other types comprising the other 17%. In a 2015 study in Sweden, type I was nearly six times more common than type III and nearly four times more common than type IV. Most people with OI receive it from a parent, but in many cases, it is a brand new (de novo or "sporadic") mutation in a family. Among a study of patients with survivable types of OI, OI type III is most often de novo (85%), followed by type IV (50%) and type I (34%). Some populations can have a higher incidence of OI than would be otherwise expected if they have a larger-than-average number of carriers of the recessive forms of the disease.
==== Chalcogenides and pnictides ==== Indium derivatives of chalcogenides (O, S, Se, Te) are well developed. Indium(III) oxide, In2O3, forms when indium metal is burned in air or when the hydroxide or nitrate is heated. The analogous sesqui-chalcogenides with sulfur, selenium, and tellurium are also known. The chemistry of indium pnictides (N, P, As, Sb) is also well known, motivated by their relevance to semiconductor technology. For applications in microelectronics, the P, As, and Sb derivatives are made by reactions of trimethylindium:
=== Industrial development === Nevertheless, as a result of industrial development, agriculture became a marginal sector. The fourth De Gasperi government established the Cassa per il Mezzogiorno, a public body tasked with financing infrastructural and industrial development to raise the region to match the rest of Italy (Law 646, 10 August 1950). The law's original 10-year term was gradually extended until 1992. It included the A.S.I. plan, which supported the creation of Industrial Development Areas. It provided for the establishment of consortia, promoted by entities such as municipalities, provinces and chambers of commerce for industrial development and basic infrastructure (Law 634, 29 July 1957 “Provvedimenti per il Mezzogiorno”). In Calabria, for example, important works were the addition of 212 km of the Battipaglia-Reggio Calabria railway line (completed in 1965). However, politicization led to poor quality and corruption (such as financing "entrepreneurs" that later turned out to be shell companies). Procurements and other state initiatives ended up creating useless infrastructure, either because they were unrealistic, or because they remained unfinished: the term "cathedral in the desert" became popular. The 1950s and 1960s became known as the period of the “economic miracle”: industrial development, economic growth, and an increase in consumption occurred. Italian industry modernized via the adoption of American technological skills and equipment financed by the Marshall Plan.
In 1867, the Straits Settlements were separated from British India, coming under the direct control of Britain. Later, in the 1890s, when the rubber industry became established in Malaya and Singapore, the island became a global centre for rubber sorting and export.
Sources: en.wikipedia.org
It is a laboratory-made peptide of forty-four amino acids whose sequence matches human growth hormone-releasing hormone, with a modified amino terminus. The modification is a short unsaturated fatty acid chain attached to the first residue. This change slows enzymatic breakdown and lengthens the time the peptide stays active in circulation.
The clinical program was designed around HIV-associated lipodystrophy, a condition in which fat accumulates abnormally around the internal organs. Trials enrolled that specific population, so the evidence base covers it rather than the general population. Regulators approved the drug for the studied indication only, and promotion outside it is not permitted.
Growth hormone therapy supplies the finished hormone directly, while this peptide acts upstream and asks the pituitary to secrete its own. That difference means the response depends on a functioning pituitary and on the body's normal feedback loops. It also means the circulating hormone profile is pulsatile rather than a flat, injected level.
多肽在反相柱上按疏水性差异分离,能有效区分主峰、缺失序列片段与氧化产物。配合紫外检测可获得可量化的纯度百分比,是肽类分析的常规手段。