Correction to: Journal of Pharmaceutical Investigation https://doi.org/10.1007/s40005-020-00480-1, https://doi.org/10.1007/s40005-020-00481-0, https://doi.org/10.1007/s40005-020-00482-z, https://doi.org/10.1007/s40005-020-00484-x

The article Emerging nanoparticulate drug delivery systems of metformin, written by Yao Chen, Xinzhu Shan, Cong Luo and Zhonggui He, was originally published Online First without Open Access. After publication in volume 50, issue 3, pages 219–230, the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution licence CC BY: This licence allows readers to copy, distribute and transmit the Article as long as it is attributed back to the author. Readers are permitted to alter, transform or build upon the Article, and to use the Article for commercial purposes. Please read the full licence for further details at http://creativecommons.org/licenses/by/4.0/.

The article Mitochondrial targeted strategies and their application for cancer and other diseases treatment, written by Qiuyi Li and Yuan Huang, was originally published Online First without Open Access. After publication in volume 50, issue 3, pages 271–293, the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution licence CC BY: This licence allows readers to copy, distribute and transmit the Article as long as it is attributed back to the author. Readers are permitted to alter, transform or build upon the Article, and to use the Article for commercial purposes. Please read the full licence for further details at http://creativecommons.org/licenses/by/4.0/.

The article Factors influencing drug deposition in the nasal cavity upon delivery via nasal sprays, written by Mingyue Gao, Xin Shen and Shirui Mao, was originally published Online First without Open Access. After publication in volume 50, issue 3, pages 251–259, the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution licence CC BY: This licence allows readers to copy, distribute and transmit the Article as long as it is attributed back to the author. Readers are permitted to alter, transform or build upon the Article, and to use the Article for commercial purposes. Please read the full licence for further details at http://creativecommons.org/licenses/by/4.0/.

The article Gene regulations and delivery vectors for treatment of cancer, written by Ming Chen, Yu-Xin Ren, Ying Xie and Wan-Liang Lu, was originally published Online First without Open Access. After publication in volume 50, issue 3, pages 309–326, the author decided to opt for Open Choice and to make the article an Open Access publication. Therefore, the copyright of the article has been changed to © The Author(s) 2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution licence CC BY: This licence allows readers to copy, distribute and transmit the Article as long as it is attributed back to the author. Readers are permitted to alter, transform or build upon the Article, and to use the Article for commercial purposes. Please read the full licence for further details at http://creativecommons.org/licenses/by/4.0/.