Darifenacin is a selective muscarinic receptor M3 antagonist which was approved by FDA for the treatment of overactive bladder.

Abacavir is a nucleoside reverse transcriptase inhibitor used for treatment of HIV infection (either alone or in combination with other antiviral drugs). It was shown that abacavir exerts its antiviral activity through its active metabolite, carbovir triphosphate. Carbovir triphosphate is a guanine analogue and a potent and selective inhibitor of viral reverse transcriptases. Upon administration, abacavir is first converted to abacavir monophosphate by ADK, then the monophosphate is deaminated to carbovir monophosphate, which is then anabolized by cellular kinases to carbovir diphosphate and then finally to carbovir triphosphate. Abacavir causes hypersensitivity reaction in patients with HLA-B*57:01 allele.

Topotecan, a semi-synthetic derivative of camptothecin (a plant alkaloid obtained from the Camptotheca acuminata tree), is an anti-tumor drug with topoisomerase I-inhibitory activity similar to irinotecan. DNA topoisomerases are enzymes in the cell nucleus that regulate DNA topology (3-dimensional conformation) and facilitate nuclear processes such as DNA replication, recombination, and repair. During these processes, DNA topoisomerase I creates reversible single-stranded breaks in double-stranded DNA, allowing intact single DNA strands to pass through the break and relieve the topologic constraints inherent in supercoiled DNA. The 3'-DNA terminus of the broken DNA strand binds covalently with the topoisomerase enzyme to form a catalytic intermediate called a cleavable complex. After DNA is sufficiently relaxed and the strand passage reaction is complete, DNA topoisomerase reattaches the broken DNA strands to form the unaltered topoisomers that allow transcription to proceed. Topotecan interferes with the growth of cancer cells, which are eventually destroyed. Since the growth of normal cells can be affected by the medicine, other effects may also occur. Unlike irinotecan, topotecan is found predominantly in the inactive carboxylate form at neutral pH and it is not a prodrug. Topotecan has the same mechanism of action as irinotecan and is believed to exert its cytotoxic effects during the S-phase of DNA synthesis. Topoisomerase I relieves torsional strain in DNA by inducing reversible single strand breaks. Topotecan binds to the topoisomerase I-DNA complex and prevents religation of these single strand breaks. This ternary complex interferes with the moving replication fork, which leads to the induction of replication arrest and lethal double-stranded breaks in DNA. As mammalian cells cannot efficiently repair these double strand breaks, the formation of this ternary complex eventually leads to apoptosis (programmed cell death). Topotecan mimics a DNA base pair and binds at the site of DNA cleavage by intercalating between the upstream (−1) and downstream (+1) base pairs. Intercalation displaces the downstream DNA, thus preventing religation of the cleaved strand. By specifically binding to the enzyme–substrate complex, Topotecan acts as an uncompetitive inhibitor. Topotecan is used for the treatment of advanced ovarian cancer in patients with disease that has recurred or progressed following therapy with platinum-based regimens. Also used as a second-line therapy for treatment-sensitive small cell lung cancer, as well as in combination with cisplatin for the treatment of stage IV-B, recurrent, or persistent cervical cancer not amenable to curative treatment with surgery and/or radiation therapy. Topotecan is sold under the trade name Hycamtin.

Docetaxel was protected by patents (U.S. patent and European patent) which were owned by Sanofi-Aventis, and so was available only under the Taxotere brand name internationally. The European patent expired in 2010. Docetaxel is a clinically well-established anti-mitotic chemotherapy medication used for the treatment of patients with locally advanced or metastatic breast cancer after failure of prior chemotherapy. Also used as a single agent in the treatment of patients with locally advanced or metastatic non-small cell lung cancer after failure of prior platinum-based chemotherapy. It is also used in combination with prednisone, in the treatment of patients with androgen independent (hormone refractory) metastatic prostate cancer. Furthermore, docetaxel has uses in the treatment of gastric adenocarcinoma and head and neck cancer. Docetaxel interferes with the normal function of microtubule growth. Whereas drugs like colchicine cause the depolymerization of microtubules in vivo, docetaxel arrests their function by having the opposite effect; it hyper-stabilizes their structure. This destroys the cell's ability to use its cytoskeleton in a flexible manner. Specifically, docetaxel binds to the β-subunit of tubulin. Tubulin is the "building block" of mictotubules, and the binding of docetaxel locks these building blocks in place. The resulting microtubule/docetaxel complex does not have the ability to disassemble. This adversely affects cell function because the shortening and lengthening of microtubules (termed dynamic instability) is necessary for their function as a transportation highway for the cell. Chromosomes, for example, rely upon this property of microtubules during mitosis. Further research has indicated that docetaxel induces programmed cell death (apoptosis) in cancer cells by binding to an apoptosis stopping protein called Bcl-2 (B-cell leukemia 2) and thus arresting its function.

Aldoxorubicin (INNO-206) is a tumor-targeted doxorubicin conjugate developed by CytRx for treating relapsed and refractory sarcomas, especially L-sarcomas. Aldoxorubicin is a rationally-engineered cytotoxic which delivers a well-established anti-cancer agent, doxorubicin, into the tumor. Currently, in late-stage clinical trials, Aldoxorubicin appears to overcome the key limitations of doxorubicin, including cumulative dose restrictions. Aldoxorubicin utilizes an acid-sensitive linker that selectively binds to albumin, which may allow the cytotoxic payload to preferentially accumulate in the tumor and potentially spare the surrounding healthy tissue. This mechanism leverages the tumor's low pH environment and accompanying dependency upon circulating albumin to fuel growth, to enable the delivery of multifold times the standard dosing of doxorubicin. The preferential uptake of Aldoxorubicin by tumor tissue and the acid sensitive release of doxorubicin allow for Aldoxorubicin to be a very promising anticancer agent. In phase I and II trials, Aldoxorubicin demonstrates superior efficacy over doxorubicin. Although the studies were not powered for OS, Aldoxorubicin shows improved PFS and tumor response in comparison to doxorubicin. The safety profile was also comparable to that of doxorubicin. Similarly, results from the recent phase III study showed a benefit in PFS in the leiomyosarcoma subtypes.

Vinflunine (Javlor) is the first fluorinated microtubule inhibitor belonging to the Vinca alkaloids family. Vinflunine, at the lowest effective concentrations, interacts with the Vinca alkaloid binding site on tubulin, suppresses microtubule dynamics (switching at microtubule ends between phases of slow growth and rapid shortening) and microtubule treadmilling (growth at the plus end and shortening at the minus end of the microtubule), causes cell cycle arrest which appears on fluorescence-activated cell sorting analysis as a G2 + M phase arrest, and is associated with an accumulation of cells in mitosis leading to cell death via apoptosis. Vinflunine has been been approved for advanced or metastatic transitional cell carcinoma of the urothelial tract. Pierre Fabre submitted an extension to the EU authorisation to add treatment of advanced breast cancer.