Talazoparib (Talzenna)

Medicine at a glance

Talazoparib is a targeted cancer medicine taken as capsules once daily. Its verified brand name is Talzenna. It belongs to a group called PARP inhibitors, which interfere with the repair of damaged DNA inside cells. Your treatment may involve talazoparib alone or talazoparib with enzalutamide, a hormone-blocking medicine. The dose and some precautions differ between these plans.

Regular blood tests are an essential part of treatment because talazoparib can substantially reduce blood-cell numbers. You may need a treatment pause, a smaller dose or a transfusion. Report fever, unusual bleeding, worsening breathlessness or marked weakness promptly. Serious illness can develop even when you are taking treatment at home and feel reasonably well between doses.

This CTI Clearly guide explains practical treatment and safety information. Your prescription, the leaflet supplied with your particular capsules and your oncology team's written plan take priority over general examples here. Keep your hospital's urgent advice details readily available.

What talazoparib is and how it works

DNA carries instructions that help cells function. Cells continually repair damage to it. PARP proteins help with part of that repair process. Talazoparib blocks their activity and can trap PARP on damaged DNA, making further repair more difficult. Cancer cells with certain existing repair weaknesses may then accumulate damage they cannot survive. Healthy cells can also be affected, particularly those producing blood cells.

BRCA1 and BRCA2 are among the genes involved in DNA repair. An inherited change in one of these genes can help identify whether talazoparib is appropriate in a particular treatment setting. Other repair genes may matter in other settings. This does not mean every gene change predicts the same benefit or that all cancers respond.

Enzalutamide blocks androgen signalling, which some cancer cells use to grow. Combining it with talazoparib affects cancer through different processes. Enzalutamide also increases talazoparib exposure in the body, which helps explain the lower talazoparib starting dose used together. Do not add, stop or change either medicine independently.

How the team decides whether it is suitable

Your oncologist considers the diagnosis, laboratory and scan results, previous treatments, blood counts, organ function and your priorities. Molecular testing may involve an inherited BRCA result or a wider panel of DNA-repair genes. An inherited result can have implications for relatives; genetic counselling can explain what it means without assuming that family members carry the same change.

Testing requirements differ between treatment settings and prescribing regions. For the enzalutamide combination, US prescribing information requires a relevant homologous recombination repair, or HRR, gene alteration. European prescribing information does not require tumour mutation testing for selection in that setting. Your team should explain which evidence and prescribing framework apply to you. A result found on the internet cannot establish eligibility.

Moderate or severe kidney impairment usually requires a lower talazoparib dose. Experience is limited with very severe kidney impairment and dialysis. Talazoparib alone does not generally require a dose change for liver impairment, but European information does not recommend its enzalutamide combination in severe liver impairment. Its safety and effectiveness in children have not been established. Tell the team about allergies to the medicine or capsule ingredients.

Before treatment starts

A full blood count checks red cells, infection-fighting white cells and platelets, which help stop bleeding. The team should allow adequate recovery from blood-count suppression caused by previous treatment before starting talazoparib. Kidney function helps determine the dose; liver tests and other blood chemistry provide a baseline for later comparisons.

Discuss previous marrow problems, transfusions, persistent infections, unexplained bruising and any earlier chemotherapy or radiotherapy. Tell the team about hepatitis or other longstanding infections so that testing and prevention can be considered for your circumstances. There is no single talazoparib-specific antiviral schedule for everyone.

If you will also take enzalutamide, disclose seizures, unexplained loss of consciousness, heart disease, high blood pressure, falls, fractures and swallowing difficulties. The team may arrange additional assessments and a bone-health plan. A pregnancy test is needed before treatment when pregnancy is possible. Discuss fertility preservation before the first dose if having children matters to you.

Bring a complete list of prescribed medicines, pharmacy remedies, vitamins and herbal products. Before leaving, confirm the capsule strength, number per dose, blood-test dates, missed-dose instructions and whom to contact out of hours.

How treatment is taken

Daily dose and schedule

Talazoparib is usually taken once daily, continuously, with or without food. A usual starting example is 1 mg daily when taken alone, or 0.5 mg daily with enzalutamide. These are examples, not a personal dosing instruction. Kidney function, side effects and interacting medicines can change the prescription. Treatment continues while it remains appropriate and tolerable; it does not have a universal fixed number of months.

With the prostate treatment combination, prescribed injections that suppress testosterone generally continue unless surgical removal of both testicles has already provided that suppression. The capsules do not automatically replace these injections.

Capsule strengths and swallowing

US information includes hard capsules and a separately labelled liquid-filled soft-capsule product, with strengths from 0.1 mg to 1 mg. The European information checked covers hard capsules in five strengths, without a single 0.75 mg capsule. A prescribed dose may therefore require several capsules. The European 0.1 mg capsule is specifically for dose modification and must not be substituted freely for other strengths. Ask the pharmacist to check any change in appearance or packaging.

Swallow capsules whole with water. Do not chew, crush, open or dissolve them. A liquid-filled capsule is still a capsule to swallow; its contents are not an oral liquid to squeeze into food. These labels do not provide a home feeding-tube method. Contact the team before the next dose if you cannot swallow safely.

Enzalutamide can also cause swallowing or choking problems because of its capsule or tablet size. Tell the team promptly; a smaller tablet may be considered. Do not force yourself to swallow a medicine that is getting stuck.

Missed doses, vomiting and errors

If you miss a dose or vomit after taking it, do not take an extra capsule or repeat the dose. Take the next prescribed dose at the usual time. Never double up to catch up. Contact the team if vomiting continues, several doses are missed or you cannot keep fluids down.

If you take too much or the wrong strength, contact your oncology service or local poison-information service immediately, even if you feel well. Take the pack with you if assessment is needed. Severe symptoms require emergency care.

Storage and handling

Keep capsules in their supplied packaging, away from children and pets. US storage instructions specify 20–25°C (68–77°F), with permitted brief excursions to 15–30°C (59–86°F); the European product has no special storage requirement. Follow your own pack and ask the pharmacist about hot-weather transport. Return unused capsules through the recommended pharmacy disposal route. Do not share them or empty them into household drains.

Monitoring and checking whether treatment is working

Blood counts are checked before treatment, at least monthly during treatment and more often when clinically necessary. If counts fall significantly, the team may pause talazoparib and repeat tests more frequently, sometimes weekly. Symptoms alone cannot reliably show whether counts are safe. Attend tests even when you feel well.

The team also reviews kidney function, other blood results, weight, appetite, side effects and any changes to your medicines. Scans and relevant disease markers help assess cancer control. The timing depends on your cancer and treatment plan. Feeling tired does not prove treatment has stopped working; feeling better does not replace objective assessment.

A lower dose is a planned safety measure when needed. Do not make the reduction yourself or restart an old dose after a break. Persistent blood-count problems need further investigation rather than repeated restarts without explanation. US information directs discontinuation and specialist blood assessment if treatment-related blood-count toxicity does not resolve within 28 days.

If enzalutamide is included, monitoring also considers blood pressure, cardiovascular health and falls or fracture risk. Ask for a revised written plan whenever either medicine changes.

Common side effects and practical management

Low blood counts

Anaemia means too few red blood cells or too little haemoglobin, the oxygen-carrying substance inside them. It can cause fatigue, dizziness, a racing heartbeat and breathlessness. Report these symptoms; treatment may include a pause, dose reduction or blood transfusion. Do not assume an iron supplement will correct treatment-related anaemia.

Low neutrophils increase infection risk. Keep hands clean, avoid close contact with people who are clearly unwell and seek urgent advice for infection symptoms. Low platelets can cause easy bruising, nosebleeds, gum bleeding or small red spots on the skin. Tell the team promptly and check before using aspirin or anti-inflammatory painkillers. Do not independently stop a prescribed blood thinner.

Fatigue and dizziness

Fatigue may reflect the medicine, cancer, anaemia, disrupted sleep or several factors together. Balance rest with gentle activity that feels manageable. Ask for help with demanding tasks and report a sudden deterioration. Sit down if dizzy and rise slowly. Do not drive or use machinery when tired or dizzy enough to affect concentration.

Nausea, vomiting and appetite changes

Take prescribed anti-sickness treatment as directed. Smaller meals and regular drinks may be easier than large portions. Food is optional with talazoparib, so discuss whether taking it with a light meal helps you. Report ongoing vomiting, poor intake or weight loss early; the team can review supportive medicines and arrange dietetic help. Do not repeat a vomited dose.

Diarrhoea, abdominal discomfort and mouth symptoms

Tell the team about loose stools and use anti-diarrhoea medicine according to their plan. Drink regularly unless you have a fluid restriction. Severe pain, blood in stools, dizziness, very little urine or inability to drink need urgent assessment. Mouth soreness or indigestion can also occur. Gentle mouth care and prescribed rinses may help; seek advice if soreness affects eating or swallowing.

Hair, headache and blood chemistry changes

Hair may thin or fall out; the extent varies. Discuss scalp care and practical support if this is distressing. Report persistent headaches, and seek emergency help for sudden severe headache with neurological symptoms. Blood tests can show changes in liver enzymes, glucose or mineral levels. Some changes are more relevant with the combination treatment, so the team interprets results in context and treats deficiencies when needed.

Important side effects

Serious infection, bleeding or anaemia

Blood-count suppression can become severe. Infection with low neutrophils can progress rapidly, and a normal temperature does not rule it out. Uncontrolled bleeding, collapse or severe breathlessness require emergency assessment. A transfusion is supportive treatment when needed; it does not by itself mean the cancer treatment has failed.

The chance of severe anaemia and transfusion differs between talazoparib alone and talazoparib with enzalutamide. Figures from one combination study should not be used to predict every patient's experience. Your recent blood results and symptoms are more useful for immediate decisions.

Delayed bone-marrow disorders

Myelodysplastic syndrome, or MDS, is a disorder in which the marrow produces abnormal blood cells. Acute myeloid leukaemia, or AML, is a blood cancer. Both have been reported in a small proportion of talazoparib-treated patients, sometimes with fatal outcomes. Prior chemotherapy and radiotherapy can also contribute to risk.

Symptoms overlap with ordinary low counts: persistent fatigue, repeated infections, breathlessness, unusual bruising or bleeding. Report symptoms that persist during a treatment break or develop after treatment. A haematologist may recommend marrow and chromosome tests if counts fail to recover. Talazoparib is permanently discontinued if MDS or AML is confirmed.

Clots and additional combination risks

Venous blood clots have been reported with talazoparib plus enzalutamide. European information specifically warns of a higher incidence with the combination than enzalutamide alone. A painful swollen leg needs urgent assessment. Sudden breathlessness, chest pain or coughing blood may indicate a clot in the lungs and require emergency care.

Enzalutamide brings separate risks, including seizures, a serious brain condition called posterior reversible encephalopathy syndrome, or PRES, reduced blood supply to the heart, falls and fractures. A seizure, sudden confusion, visual loss or severe chest pain needs emergency assessment. Serious allergic swelling can affect breathing or swallowing. Do not take another dose while a severe suspected reaction is being assessed; obtain immediate medical help and clinician instructions about both medicines. US guidance requires permanent discontinuation of enzalutamide after a seizure and discontinuation for confirmed PRES. These decisions belong to the treating team.

Other medicines, supplements and vaccinations

Talazoparib is affected by transport proteins called P-gp and BCRP, which influence how medicines move through the body. Medicines such as clarithromycin, itraconazole, amiodarone, carvedilol and verapamil can increase exposure. US guidance advises avoiding the listed medicines with talazoparib alone; if essential, a clinician-directed dose reduction is needed. With enzalutamide, US guidance recommends monitoring, while European guidance recommends avoiding P-gp inhibitors where possible and monitoring if unavoidable. Check every new medicine with the oncology pharmacist.

European guidance also advises avoiding strong BCRP inhibitors, including concentrated curcumin products and ciclosporin where possible. St John's wort and some seizure medicines may reduce talazoparib exposure. Tell the pharmacist about supplements sold as turmeric extracts or cancer remedies; a supplement label does not establish safety.

Acid-reducing medicines such as proton-pump inhibitors do not have a standard talazoparib separation requirement in the reviewed information. Do not impose another cancer medicine's fasting or antacid rules on this one. Enzalutamide has its own extensive interactions, including effects on other medicines. It can also produce falsely high digoxin results with certain blood-test methods. If you take digoxin, tell the team and laboratory about enzalutamide so that they can use an appropriate test and interpret results correctly. The pharmacist must check the whole combination.

Discuss vaccination timing with the team. Non-live vaccines may be recommended, while live vaccines may be unsuitable when immunity is reduced. Check before travel vaccinations. Do not start antibiotics, anti-sickness drugs or herbal products left over from an earlier treatment without advice.

Everyday life during treatment

Keep a simple record of doses, side effects and appointments. A phone reminder can help, but mark a dose as taken only after swallowing it. Arrange repeat prescriptions before the supply runs out, and keep written instructions when the capsule strength changes.

Eat as comfortably as possible and tell the team about weight loss. Gentle walking or other suitable activity can help maintain function, but avoid activities with a high injury risk when platelets are low. People receiving enzalutamide may need additional advice to reduce falls and protect bone health.

Work arrangements may need to change around fatigue, blood tests or transfusions. Before travelling, confirm access to urgent care, enough medicine and safe storage. Tell dentists and surgeons about treatment; recent blood counts may affect procedures. Talazoparib does not have one universal surgical-stop interval in the reviewed labels, so obtain an individual plan.

Ask for support with anxiety, sleep, intimacy or the impact on family life. These concerns are legitimate parts of cancer care. Driving decisions depend on symptoms and accompanying medicines; enzalutamide's seizure risk needs specific discussion even if talazoparib alone has not caused dizziness.

Fertility, contraception, pregnancy and breastfeeding

Talazoparib can harm a developing baby. A pregnancy test is required before starting when pregnancy is possible. Use effective contraception during treatment and for at least 7 months after the last dose. European guidance specifies highly effective contraception and, for patients with breast cancer, two complementary non-hormonal methods. Have the team help choose a suitable combination; do not rely on absent periods as proof that pregnancy cannot occur.

Male patients with a partner who could become pregnant, or who is pregnant, need effective contraception during treatment and for at least 4 months afterwards. European information makes clear that precautions still apply after vasectomy. Ask about the specific barrier and pregnancy-prevention arrangements appropriate for you. Report a possible pregnancy promptly.

Do not breastfeed during treatment or for at least 1 month after the last dose. Human fertility data are limited; animal findings suggest that male fertility may be affected. Discuss sperm, egg or embryo preservation before treatment where relevant. Follow any longer precautions needed for accompanying medicines rather than shortening them to the talazoparib interval.

After treatment finishes

Ask which blood tests and cancer assessments will continue, when supportive medicines can stop and who will manage symptoms. Blood counts may take time to recover. Continue contraception and breastfeeding restrictions for the full specified periods, including after a short course stopped because of side effects.

Report persistent bruising, repeated infections, unexplained fatigue or breathlessness after treatment. These symptoms have several possible causes, but delayed marrow problems should not be overlooked. Return unused capsules to the pharmacy and do not restart leftovers if symptoms or scan results change.

Frequently asked questions