FDA Approves Erleada (apalutamide) for Non-Metastatic Castration-Resistant Prostate Cancer

The U.S. Food and Drug Administration, has approved Erleada (apalutamide) for the treatment of patients with prostate cancer that has not spread (non-metastatic), but that continues to grow despite treatment with hormone therapy (castration-resistant). This is the first FDA-approved treatment for non-metastatic, castration-resistant prostate cancer.

“The FDA evaluates a variety of methods that measure a drug’s effect, called endpoints, in the approval of oncology drugs. This approval is the first to use the endpoint of metastasis-free survival, measuring the length of time that tumors did not spread to other parts of the body or that death occurred after starting treatment,” said Richard Pazdur, M.D., director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “In the trial supporting approval, Erleada had a robust effect on this endpoint. This demonstrates the agency’s commitment to using novel endpoints to expedite important therapies to the American public."

According to the National Cancer Institute (NCI) at the National Institutes of Health, prostate cancer is the second most common form of cancer in men in the U.S.. The NCI estimates approximately 161,360 men were diagnosed with prostate cancer in 2017, and 26,730 were expected to die of the disease. Approximately 10 to 20 percent of prostate cancer cases are castration-resistant, and up to 16 percent of these patients show no evidence that the cancer has spread at the time of the castration-resistant diagnosis.

Erleada works by blocking the effect of androgens, a type of hormone, on the tumor. These androgens, such as testosterone, can promote tumor growth.

The safety and efficacy of Erleada was based on a randomized clinical trial of 1,207 patients with non-metastatic, castration-resistant prostate cancer. Patients in the trial either received Erleada or a placebo. All patients were also treated with hormone therapy, either with gonadotropin-releasing hormone (GnRH) analog therapy or with surgery to lower the amount of testosterone in their body (surgical castration). The median metastasis-free survival for patients taking Erleada was 40.5 months compared to 16.2 months for patients taking a placebo.

Common side effects of Erleada include fatigue, high blood pressure (hypertension), rash, diarrhea, nausea, weight loss, joint pain (arthralgia), falls, hot flush, decreased appetite, fractures and swelling in the limbs (peripheral edema).

Severe side effects of Erleada include falls, fractures and seizures.

This application was granted Priority Review, under which the FDA’s goal is to take action on an application within 6 months where the agency determines that the drug, if approved, would significantly improve the safety or effectiveness of treating, diagnosing or preventing a serious condition.

The sponsor for Erleada is the first participant in the FDA’s recently-announced Clinical Data Summary Pilot Program, an effort to provide stakeholders with more usable information on the clinical evidence supporting drug product approvals and more transparency into the FDA’s decision-making process. Soon after approval, certain information from the clinical summary report will post with the Erleada entry on Drugs@FDA and on the new pilot program landing page.

FDA Approves Erleada (apalutamide) for Non-Metastatic Castration-Resistant Prostate Cancer

FDA Approves Symdeko (tezacaftor/ivacaftor and ivacaftor) to Treat Cystic Fibrosis in People Ages 12 and Older with Certain Mutations in the CFTR Gene

Vertex Pharmaceuticals Incorporated announced  the U.S. Food and Drug Administration (FDA) approval of  Symdeko (tezacaftor/ivacaftor and ivacaftor) for treating the underlying cause of cystic fibrosis (CF) in people ages 12 and older who have two copies of the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene or who have at least one mutation that is responsive to tezacaftor/ivacaftor. Symdeko is Vertex's third medicine approved to treat the underlying cause of CF. Vertex is ready to launch Symdeko and will begin shipping it to pharmacies in the United States this week.

Ivacaftotezacaftor

"Today is an exciting day for the CF community. The approval of Symdeko, our third disease-modifying CF medicine, offers many patients an important new treatment option," said Jeffrey Leiden, M.D., Ph.D., Vertex's Chairman, President and Chief Executive Officer. "This approval is an important milestone in our journey to treat every person with CF, and we remain committed to urgently advancing our efforts to develop new medicines that treat the underlying cause of CF for the many people still waiting."

In November 2017, the New England Journal of Medicine published the results of two Phase 3 studies of Symdeko. These studies, named EVOLVE and EXPAND, enrolled approximately 750 people with CF ages 12 and older with two copies of the F508del mutation or with one F508del mutation and one mutation that results in residual CFTR function. Across both studies, patients treated with Symdeko experienced statistically significant and clinically meaningful improvements in lung function and other measures of disease, with a favorable safety profile. The most common adverse events, regardless of treatment group, included infective pulmonary exacerbation and cough. The first data from the ongoing EXTEND rollover study, also presented in November, show that the lung function improvements and the safety and tolerability profiles seen in EVOLVE and EXPAND were sustained for up to 48 total weeks of Symdeko treatment.

"We've already seen the significant impact that disease-modifying medicines can have on patients and are incredibly pleased that there is now a third treatment option that enables more patients to benefit from CFTR modulation," said Patrick Flume, M.D., Director of the Medical University of South Carolina Cystic Fibrosis Center and Principal Investigator for the EXTEND study. "In particular, Symdeko is an important treatment option for patients who either never started or discontinued Orkambi, and it also provides increased benefit over Kalydeco alone for patients with residual function mutations."

The European Medicines Agency (EMA) has validated the Marketing Authorization Application (MAA) for the tezacaftor/ivacaftor combination. The company expects approval in the EU in the second half of 2018.

FDA Approves Symdeko (tezacaftor/ivacaftor and ivacaftor) to Treat Cystic Fibrosis in People Ages 12 and Older with Certain Mutations in the CFTR Gene

CutisPharma Announces FDA Approval of Firvanq (vancomycin) for Treatment of Clostridium Difficile Associated Diarrhea and Staphylococcus Aureus Colitis

In continuation of my update on vancomycin

CutisPharma announced  the US Food and Drug Administration (FDA)  approval of  Firvanq (vancomycin hydrochloride) for oral solution, for the treatment of Clostridium difficile associated diarrhea and enterocolitis caused by Staphylococcus aureus, including methicillin-resistant strains.

“We are pleased to announce the FDA approval of Firvanq,” said Neal I. Muni, MD, MSPH, Chief Executive Officer of CutisPharma. “Firvanq's approval is an important step forward to providing patients the only FDA-approved vancomycin oral liquid treatment option for Clostridium difficile associated diarrhea, a life-threatening condition that affects over a half-million patients in the United States annually.”

Upon its launch, which is targeted to be April 2, 2018, Firvanq will replace CutisPharma’s FIRST®-Vancomycin Unit-of-Use Compounding Kit, which has been available to pharmacists that need a convenient, accurate, and compliant way to compound vancomycin oral liquid therapy. Firvanq will be commercially available in 25 mg/mL and 50 mg/mL strengths in convenient 150 mL and 300 mL sizes. Firvanq is designed to be easy to use and has the potential to be a cost-effective alternative to existing vancomycin therapies.

“As a practicing infectious disease physician treating many patients with CDAD, having an FDA-approved vancomycin oral liquid formulation that is affordable and accessible to my patients is very beneficial,” said Stuart Johnson, MD, Loyola University Medical Center. “Patient access is currently limited by the fact that only a select few pharmacies perform compounding in the outpatient setting these days, given the many new regulations in place. Availability of an FDA-approved vancomycin oral liquid treatment will effectively allow any pharmacy to stock this therapy, and hopefully encourage third-party payer reimbursement, significantly improving accessibility and convenience for patients.”

CutisPharma Announces FDA Approval of Firvanq (vancomycin) for Treatment of Clostridium Difficile Associated Diarrhea and Staphylococcus Aureus Colitis

FDA Approves Osmolex ER (amantadine) for the treatment of Parkinson’s Disease and Drug-Induced Extrapyramidal Reactions

 

In continuation of my update on amantadine

Osmotica Pharmaceutical US LLC, announced the  U.S. Food and Drug Administration (FDA) has approval Osmolex ER, an amantadine extended release tablet, for the treatment of Parkinson's disease and for the treatment of drug-induced extrapyramidal reactions in adult patients. Extrapyramidal symptoms are known side effects of many common medications.

“The FDA’s approval of Osmolex ER provides a new treatment option for those patients suffering from Parkinson’s disease and adults who have extrapyramidal reactions, or movement disorders, that are caused by certain medicines. We are eager to make Osmolex ER available to physicians and patients in the U.S.,” stated Brian Markison, Chief Executive Officer of Osmotica.

“We are currently finalizing our plans to commercialize the product and ensure patients and providers have access as soon as possible. We believe that the approved indications and compelling value proposition will be important factors in physician adoption and marketing of Osmolex ER,” added Markison.

Osmolex ER tablets, a proprietary drug formulation containing a combination of immediate release and extended release amantadine utilizing Osmotica’s patented Osmodex® technology, represents a new once-a-day approach to the treatment of Parkinson’s disease and drug-induced involuntary movements in adults. The Osmolex ER tablet is taken once-daily in the morning, releasing amantadine throughout the day. Physicians have three dosage options with 129 mg, 193 mg and 258 mg tablets, with a maximum daily dose of 322 mg, providing them with dosing flexibility for each patient.

Osmolex ER is protected by three formulation patents with protection extending through March 2030, with additional patent applications pending.

FDA Approves Osmolex ER (amantadine) for the treatment of Parkinson’s Disease and Drug-Induced Extrapyramidal Reactions

New class of antimicrobial polymers can kill five hard-to-treat multidrug-resistant bacteria

An international research team led by the Institute of Bioengineering and Nanotechnology (IBN) of the Agency for Science, Technology and Research (A*STAR) and IBM Research developed a synthetic molecule that can kill five deadly types of multidrug-resistant bacteria with limited, if any, side effects. Their new material could be developed into an antimicrobial drug to treat patients with antibiotic-resistant infections. This finding was reported in the scientific journal Nature Communications.

Superbugs that are resistant to antibiotics are a serious health threat. According to the UK Review on Antimicrobial Resistance, superbugs kill around 700,000 people worldwide each year. By 2050, 10 million people could die each year if existing antibiotics continue to lose their effectiveness.

“There is an urgent global need for new antimicrobials that are effective against superbugs. The situation has become more acute because bacteria are starting to develop resistance to the last-line antibiotics, which are given only to patients infected with bacteria resistant to available antibiotics,” said Professor Jackie Y. Ying, Executive Director of IBN.

The research community is trying to develop alternatives to antibiotics using synthetic polymers. However, the antimicrobial polymers developed so far are either too toxic for clinical use, not biodegradable or can only target one type of bacteria.

To address this problem, Dr Yi Yan Yang from IBN brought together a multidisciplinary research team from the US, China and Singapore to develop a new class of antimicrobial polymers called guanidinium-functionalized polycarbonates with a unique killing mechanism that can target a broad range of multidrug-resistant bacteria. It is biodegradable and non-toxic to human cells.

The polymer kills bacteria in the following way. First, the polymer binds specifically to the bacterial cell. Then, the polymer is transported across the bacterial cell membrane into the cytoplasm, where it causes precipitation of the cell contents (proteins and genes), resulting in cell death.

The team tested the polymers on mice infected with five hard-to-treat multidrug-resistant bacteria: Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, methicillin-resistant Staphylococcus aureu and Pseudomonas aeruginosa. These superbugs are commonly acquired by patients in the hospitals and can cause systemic infections that lead to septic shock and multiple organ failure. The results showed that the bacteria were effectively removed from the mice and no toxicity was observed.

The researchers then further tested the effectiveness of the polymers on mice with two types of systemic infections caused by superbugs: peritonitis (an infection of the stomach’s inner lining) and lung infections from Pseudomonas aeruginosa. The polymers eliminated the bacterial infections in both groups of mice with negligible toxicity.

Dr Yi Yan Yang, Group Leader at IBN said:

We have demonstrated the first example of a biodegradable synthetic macromolecule with broad-spectrum antimicrobial activity in mice, unique killing mechanism and no toxicity. Once the polymer finishes its job of killing the bacteria, it will be naturally degraded after three days and will not remain in the body. This antimicrobial agent shows great promise for the treatment and prevention of multidrug-resistant systemic infections.

“This study illustrates the potential for this new research field we denote as ‘macromolecular therapeutics’ to create entirely new classes of treatments for multiple diseases,” said Dr James Hedrick, Distinguished Research Staff Member, IBM Research – Almaden, San Jose, California. “In 2016, we demonstrated the efficacy of synthetic polymers to combat deadly viral diseases. The current research for treating bacterial infections rounds out our ability to someday treat a spectrum of infectious diseases with a single, new type of mechanism without the onset of resistance.”

To determine whether the bacteria will develop any resistance to the polymer, the team collaborated with Dr Paola Florez de Sessions at A*STAR’s Genome Institute of Singapore and the Cell Engineering group of Dr Simone Bianco at IBM Research – Almaden to perform genomic analysis. They found that the bacteria did not show any resistance development even after multiple treatments with the polymer.

Ref :http://www.ibn.a-star.edu.sg/pdf/media_release/press_133.pdf

https://www.nature.com/articles/s41467-018-03325-6/figures/1

New class of antimicrobial polymers can kill five hard-to-treat multidrug-resistant bacteria

Antiviral drug not beneficial for reducing mother-to-child transmission of hepatitis B when added to existing preventatives

In continuation of my update on Tenofovir

Tenofovir disoproxil fumarate (TDF), an antiviral drug commonly prescribed to treat hepatitis B infection, does not significantly reduce mother-to-child transmission of hepatitis B virus when taken during pregnancy and after delivery, according to a phase III clinical trial in Thailand funded by the National Institutes of Health. The study tested TDF therapy in addition to the standard preventative regimen — administration of hepatitis B vaccine and protective antibodies at birth — to explore the drug’s potential effects on mother-to-child transmission rates. The results appear in the New England Journal of Medicine.

“Limited evidence of the benefit of using antiviral drugs to prevent mother-to-child transmission of hepatitis B has led to conflicting practice recommendations around the world,” said Nahida Chakhtoura, M.D., a study team member and medical officer at NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). “Our study suggests that adding TDF to the current regimen seems to have little effect on infant infection rates when transmission rates are already low.”

To prevent infection, WHO recommends that all newborns receive their first dose of hepatitis B vaccine within 24 hours of delivery. Infants born to hepatitis B-infected mothers are also given protective antibodies called hepatitis B immune globulin (HBIG). However, mother-to-child transmission can still occur in women with high levels of virus in their blood, as well as those with mutated versions of the virus.

The current study was conducted at 17 hospitals of the Ministry of Public Health in Thailand. It screened more than 2,500 women for eligibility and enrolled 331 pregnant women with hepatitis B. The women received placebo (163) or TDF (168) at intervals from 28 weeks of pregnancy to two months after delivery. All infants received standard hepatitis B preventatives given in Thailand, which include HBIG at birth and five doses of the hepatitis B vaccine by age 6 months (which differs from the three doses given in the United States). A total of 294 infants (147 in each group) were followed through age 6 months.

Three infants in the placebo group had hepatitis B infection at age 6 months, compared to zero infants in the TDF treatment group. Given the unexpectedly low transmission rate in the placebo group, the researchers concluded that the addition of TDF to current recommendations did not significantly reduce mother-to-child transmission of the virus.

“We observed no treatment-related safety concerns for the mothers or infants and no significant differences in infant growth,” said the study’s lead author Gonzague Jourdain, M.D., Ph.D., of Thailand’s Chiang Mai University, the Harvard T.H. Chan School of Public Health and France’s IRD (Institut de recherche pour le développement). “These safety data also are relevant for pregnant women receiving TDF as part of HIV treatment or HIV pre-exposure prophylaxis.”

According to the study authors, the clinical trial had enough participants to detect statistical differences if the transmission rate in the placebo group reached at least 12 percent, a rate observed in previous studies. Though the reasons are unknown, the researchers speculate that the lower transmission rate seen in the study may relate to the number of doses of hepatitis B vaccine given to infants in Thailand, lower rates of amniocentesis and Cesarean section deliveries in this study, or the lower prevalence of mutated viruses that result in higher vaccine efficacy in Thailand compared to other countries.

Ref : http://www.nejm.org/doi/full/10.1056/NEJMoa1708131

Antiviral drug not beneficial for reducing mother-to-child transmission of hepatitis B when added to existing preventatives

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease

The supplement nicotinamide riboside (NR) – a form of vitamin B3 – prevented neurological damage and improved cognitive and physical function in a new mouse model of Alzheimer’s disease. The results of the study, conducted by researchers at the National Institute on Aging (NIA) part of the National Institutes of Health, suggest a potential new target for treating Alzheimer’s disease. The findings appear in the Feb. 5, 2018, issue of Proceedings of the National Academy of Sciences.

NR acts on the brain by normalizing levels of nicotinamide adenine dinucleotide (NAD+), a metabolite vital to cellular energy, stem cell self-renewal, resistance to neuronal stress and DNA repair. In Alzheimer’s disease, the brain’s usual DNA repair activity is impaired, leading to mitochondrial dysfunction, lower neuron production, and increased neuronal dysfunction and inflammation.

“The pursuit of interventions to prevent or delay Alzheimer’s and related dementias is an important national priority,” said Richard J. Hodes, M.D., director of the NIA. “We are encouraging the testing of a variety of new approaches, and this study’s positive results suggest one avenue to pursue further.”

The international team of scientists was led by Vilhelm A. Bohr, M.D., Ph.D., senior investigator and chief of the Laboratory of Molecular Gerontology of the NIA’s Intramural Research Program, with Dr. Yujun Hou, a postdoctoral investigator in the laboratory.

Based on their studies in human postmortem brain, they developed a new strain of mice mimicking major features of human Alzheimer’s such as tau pathology, failing synapses, neuronal death and cognitive impairment. Using this animal model, the researchers tested the effects of an NR supplement by adding it to the drinking water of the mice. Over a three-month period, researchers found that mice who received NR showed reduced tau in their brains, but no change in amyloid-beta.

The NR-treated mice also had less DNA damage, higher neuroplasticity (activity and reorganization of brain cells associated with learning or memory), increased production of new neurons from neuronal stem cells, and lower levels of neuronal damage and death. In the hippocampus area of the brain – in which damage and loss of volume is found in people with dementia – NR seemed to either clear existing DNA damage or prevent it from spreading further.

The NR-treated mice also performed better than control mice on multiple behavioral and memory tests, such as water mazes and object recognition. NR mice also showed better muscular and grip strength, higher endurance, and improved gait compared to their control counterparts. The research team believes that these physical and cognitive benefits are due to a rejuvenating effect NR had on stem cells in both muscle and brain tissue.

“We are encouraged by these findings that see an effect in this Alzheimer’s disease model,” said Dr. Bohr. “We are looking forward to further testing of how NR or similar compounds might be pursued for their possible therapeutic benefit for people with dementia.”

Next steps for the research team include further studies on the underlying mechanisms and preparations towards intervention in humans.

The team’s work also included contributions from researchers at the Danish Aging Research Center at the University of Aarhus, and the Center for Healthy Aging at the University of Copenhagen. The Bohr lab has a Cooperative Research and Development Agreement -- which allows NIH investigators to join colleagues from industry and academia to pursue common research goals -- with ChromaDex Corp.

Compound prevents neurological damage, shows cognitive benefits in mouse model of Alzheimer’s disease

Aspirin as Good a Clot Buster as Pricey Drugs After Joint Replacement

Good old aspirin is just as effective as newer, expensive drugs at preventing blood clots after hip or knee replacement, a new clinical trial suggests.

Researchers said the findings could change some doctors' prescribing habits.

After knee or hip replacement surgery, there's a risk of blood clots in the legs or lungs. So it's routine for patients to take clot-preventing drugs for some time afterward.

Right now, some doctors choose powerful anti-clotting drugs like dabigatran (Pradaxa) and rivaroxaban(Xarelto), said Dr. David Anderson, the lead researcher on the new trial.

But it hasn't been clear whether those expensive prescription drugs are any better than cheap, readily available aspirin, explained Anderson, of Dalhousie University, in Halifax, Canada.

Based on the new findings, they're not.

Few patients in the study developed a blood clot after surgery, and those on aspirin fared just as well as those on rivaroxaban.

The caveat, Anderson said, was that all study patients received rivaroxaban for the first five days after surgery. After that, they either continued on the drug or switched to aspirin for another nine to 30 days.

"From this study, we have no evidence to support starting aspirin on day one," Anderson said.

But after day five, he added, "it's very reasonable to consider switching to aspirin."

Over the past decade, surgeons have already been turning away from powerful anticoagulants toward aspirin and non-drug options for thwarting clots, said Dr. Alejandro Gonzalez Della Valle.

Gonzalez Della Valle specializes in hip and knee surgery at the Hospital for Special Surgery in New York City.

These days, he said, patients have a generally low risk of blood clots after hip or knee replacement for a number of reasons. Those include shorter surgical times, and the use of regional anesthesia instead of general.

Clots can also be prevented by improving blood flow in patients' legs right after surgery. So getting patients on their feet and moving early on is key, Gonzalez Della Valle explained. Similarly, pneumatic compression devices can be used to encourage blood flow in the lower limbs while patients are in their hospital beds.

Dr. Kevin Bozic, a spokesperson for the American Academy of Orthopaedic Surgeons (AAOS), said that the AAOS guidelines already state that no one drug is better than another for preventing clots.

"This study reinforces that," Bozic said.

He agreed that most surgeons have been turning to aspirin in the past 10 years because recovery times are shorter and people leave the hospital much sooner. Most people can have just aspirin, but some at high risk of blood clots -- those with a history of clots, people who are very obese -- might need an anticoagulant, Bozic added.

"The strategy for preventing clots should include medication and early mobilization," he stressed.

Ref:http://www.nejm.org/doi/full/10.1056/NEJMoa1712746

Aspirin as Good a Clot Buster as Pricey Drugs After Joint Replacement - Drugs.com MedNews

Research shows link between fluoroquinolone antibiotics and increased risk of aortic disease

New research from a Swedish and Danish team of researchers led from Karolinska Institutet lend additional support to a link between treatment with fluoroquinolone antibiotics and an increased risk of acute aortic disease. The study is published in the esteemed journal The BMJ.

Fluoroquinolone antibiotics are used globally to treat a variety of infections. Recent observational studies have raised concerns that they may be associated with a more than twofold increase in the risk of acute and life-threatening aortic disease (aortic aneurysm or dissection). However, due to limitations in study design, it has not been possible to draw firm conclusions.

To assess whether there actually is a link, researchers from Karolinska Institutet and Lund University in Sweden and Statens Serum Institut in Denmark analysed data from Swedish national health registers. The researchers were then able to compare the risk of aortic aneurysm or dissection among more than 360,000 treatment episodes of fluoroquinolones with the risk among the same number of treatment episodes of amoxicillin, another type of antibiotic.

Research shows link between fluoroquinolone antibiotics and increased risk of aortic disease

High vitamin D levels may help prevent cancer

In continuation of my update on Vitamin D, 

The study reinforces the existing theory that vitamin D helps defend against certain cancers. Exposure to sunlight stimulates the production of vitamin D by our skin. Vitamin D contributes to calcium level maintenance in our bodies, which in turn helps teeth, muscles and bones remain healthy. Aside from established benefits of vitamin D on bone diseases, evidence continues to emerge that vitamin D could be effective for other cancers and chronic diseases.   

Yet more comprehensive research needs to be conducted, as to date, the majority of studies have been conducted throughout American and European populations, and more studies focusing on Asian populations are necessary.
It is vital to determine whether the effects are the same in non-Caucasian populations, since Vitamin D metabolism and concentrations differ dependant on ethnicity.
The study published by the BMJ was carried out to determine if vitamin D was linked to site specific and total cancer.

Data spanning nine public health centres across Japan was analysed, from 33,736 female and male participants between the ages of 40 and 69 years old.
Participants were required to disclose a comprehensive overview of their lifestyle, diet and medical history and have blood samples taken to assess their vitamin D levels. Factors such as seasons affected vitamin D levels; summer and autumn typically produced higher levels compared to spring or winter. Samples were then assigned to one of four groups, based on levels.

Researchers then monitored the study participants for a mean period of 16 years, during which 3,301 new cancer cases were registered.
Once multiple known cancer risk factors had been accounted for, including weight (BMI), physical activity, age, dietary factors, smoking and alcohol intake, researchers discovered that high levels of vitamin D  reduced the overall risk of cancer by 20% in both women and men.

Higher levels were linked to a 30-50% lower relative risk of liver cancer, and more so in men than women. No cancers exhibited a higher risk connected to high vitamin D levels, and there was no evidence of a link to prostate or lung cancer.
Adjustments were made for dietary and other factors to confirm the strength of the findings, but this did little to affect the results. One limitation of the study was an insufficient number of organ specific cancers. In addition, even with the risk factor adjustments, there is no absolute certainty that the results were skewed by unidentified factors.  For this reason, no concrete conclusions about cause and effect can be asserted.

The large sample size for overall cancer, large number of blood samples tested and the extensive follow up period were vital strengths of the study. The result reinforce the theory that vitamin D has a role in defending against the risk of cancer, but the authors emphasize that vitamin D may carry additional health benefits too, that were not measured in this study.  

Further studies are needed to clarify the optimal concentrations (of vitamin D) for cancer prevention."

Further studies are needed to clarify the optimal concentrations (of vitamin D) for cancer prevention."

Ref : https://www.eurekalert.org/pub_releases/2018-03/b-hvd030618.php

High vitamin D levels may help prevent cancer