It is the most frequent type of natural strabismus not only in humans, but also in monkeys.Concomitant esotropia can itself be subdivided into esotropias that are either constant, or intermittent. Constant esotropia
A constant esotropia, as the name implies, is present all the time. Intermittent esotropia
Intermittent esotropias, again as the name implies, are not always present. In very rare cases, they may only occur in repeated cycles of one day on, one day off (Cyclic Esotropia). However, the vast majority of intermittent esotropias are accommodative in origin.A patient can have a constant esotropia for reading, but an intermittent esotropia for distance (but rarely vice versa). Accommodative esotropia
Accommodative esotropia (also called refractive esotropia) is an inward turning of the eyes due to efforts of accommodation. It is often seen in patients with moderate amounts of hyperopia. The person with hyperopia, in an attempt to "accommodate" or focus the eyes, converges the eyes as well, as convergence is associated with activation of the accommodation reflex. The over-convergence associated with the extra accommodation required to overcome a hyperopic refractive error can precipitate a loss of binocular control and lead to the development of esotropia.The chances of an esotropia developing in a hyperopic child will depend to some degree on the amount of hyperopia present. Where the degree of error is small, the child will typically be able to maintain control because the amount of over-accommodation required to produce clear vision is also small.
Mitapivat, sold under the brand name Pyrukynd, is a medication used to treat hemolytic anemia. It is taken as the sulfate hydrate salt by mouth. Mitapivat is a pyruvate kinase activator.Mitapivat was approved for medical use in the United States in February 2022. Medical uses
Mitapivat is indicated for the treatment of hemolytic anemia in adults with pyruvate kinase deficiency. Pharmacology
Mechanism of action
Mitapivat binds to and activates pyruvate kinase, thereby enhancing glycolytic pathway activity, improving adenosine triphosphate (ATP) levels and reducing 2,3-diphosphoglycerate (2,3-DPG) levels. Mutations in pyruvate kinase cause deficiency in pyruvate kinase which prevents adequate red blood cell (RBC) glycolysis, leading to a buildup of the upstream glycolytic intermediate 2,3-DPG and deficiency in the pyruvate kinase product ATP. Society and culture
Legal status
On 15 September 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Pyrukynd, intended for the treatment of an inherited condition called pyruvate kinase deficiency. The applicant for this medicinal product is Agios Netherlands B.V.

Names
Mitapivat is the international nonproprietary name (INN). References
Further reading
Kung C, Hixon J, Kosinski PA, Cianchetta G, Histen G, Chen Y,  et al. (September 2017). "AG-348 enhances pyruvate kinase activity in red blood cells from patients with pyruvate kinase deficiency". Blood. 130 (11): 1347–1356. doi:10.1182/blood-2016-11-753525. PMC 5609468. PMID 28760888. Rab MA, Van Oirschot BA, Kosinski PA, Hixon J, Johnson K, Chubukov V,  et al. (January 2021).